Journal articles: 'Short-range order parameter'

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Davids, William J., Anna V. Ceguerra, and Simon P. Ringer. "Interpreting the Simplified Multicomponent Short-Range Order Parameter." Microscopy and Microanalysis 25, S2 (2019): 332–33. http://dx.doi.org/10.1017/s1431927619002393.

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Andriushchenko, Petr Dmitrievich, and Konstantin V. Nefedev. "Order Parameter in Short-Range and Long-Range Ising Finite Feromagnetic Models." Solid State Phenomena 247 (March 2016): 153–57. http://dx.doi.org/10.4028/www.scientific.net/ssp.247.153.

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The approach to determination of the order parameter in the finite 1D Ising model was proposed. For such systems a root mean square magnetization and an average size of the maximal ground state cluster which is formed by neighboring spins with an energy {-2J} does not disappear at T!=0. The temperature dependence of heat capacity and its derivative with respect to temperature from the average size of the maximum quasi ground state cluster, formed by the neighboring spins with an energy {-2J,0} in the 1D Ising chain were considered. The percolation approach in Curie-Weiss does not work due the internal structure of the model.

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Salomons, E., N. Koeman, J. Rector, and R. Griessen. "Short-range order parameter of the disordered alloy Pd91Y9determined from hydrogen absorption." Journal of Physics: Condensed Matter 2, no. 4 (1990): 835–44. http://dx.doi.org/10.1088/0953-8984/2/4/005.

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4

Singh, R. N. "Short-range order and concentration fluctuations in binary molten alloys." Canadian Journal of Physics 65, no. 3 (1987): 309–25. http://dx.doi.org/10.1139/p87-038.

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The quasi-chemical theory and the quasi-lattice theory are discussed with a view to obtaining information about concentration fluctuations, SCC(0), and the short-range order parameter, α1, for regular and compound-forming molten alloys. The influence of the coordination number z and the interchange energy ω on the mixing properties of the alloy is critically examined. SCC(0) and α1 have been found to be very useful in extracting microscopic information, like local ordering and segregation in molten systems. The problem of glass formation in compound-forming binary molten alloys is also briefly discussed.

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BONDARCHUCK, O., S. GOYSA, I. KOVAL, P. MEL'NIK, and M. NAKHODKIN. "SHORT-RANGE ORDER OF DISORDERED SOLID SURFACES FROM ELASTICALLY SCATTERED ELECTRON SPECTRA." Surface Review and Letters 04, no. 05 (1997): 965–67. http://dx.doi.org/10.1142/s0218625x97001139.

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The diffraction phenomenon of low- and middle-energy electrons for disordered solid surfaces was experimentally studied and a new electron spectroscopy technique for surface short-range order parameter determination proposed.

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Idczak, Rafał, and Robert Konieczny. "Temperature dependence of the short-range order parameter for Fe0.90Cr0.10 and Fe0.88Cr0.12 alloys." Nukleonika 60, no. 1 (2015): 35–38. http://dx.doi.org/10.1515/nuka-2015-0009.

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Abstract The 57Fe Mössbauer spectra for the iron-based solid solutions Fe0.90Cr0.10 and Fe0.88Cr0.12 were measured at different temperatures ranging from 300 K to 900 K. Analysis of the obtained spectra shows that the distribution of impurity atoms in the two first coordination shells of 57Fe nuclei is not random and it cannot be described by the binomial distribution. Quantitatively, the effects were described in terms of the atomic short-range order (SRO) parameters and the pair-wise interaction energy with the help of a quasi-chemical type formulation introduced by Cohen and Fine. The obtained results reveal strong clustering-type correlations in the studied samples (a predominance of Fe-Fe and Cr-Cr bonds). Moreover, the changes in SRO values observed during thermal processing suggest that the distribution of Cr atoms in an α-iron matrix is strongly temperature dependent.

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Bairova, G. D., and A. A. Mirzoev. "Short-Range Order in Fe-Cr Alloys: Lattice Monte Carlo Modelling." Materials Science Forum 989 (May 2020): 68–73. http://dx.doi.org/10.4028/www.scientific.net/msf.989.68.

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Short-range order in Fe–Cr alloys is investigated by Monte Carlo method. The modelling was performed by Metropolis algorithm using the LAMMPS software package. Modelling results were analyzed by the visualization and data analysis package Ovito. The model of the alloys supposed that the lattice structure was fixed and interaction exists between the first and the second neighbours. The Fe–Cr interaction was established with the use of interatomic interaction potential Abell–Brenner–Tersoff (ABOP). Different concentrations of substitutional impurity of chromium in iron were investigated, viz. 5–50 at. %. The energy of mixing in the Fe–Cr system was calculated for various concentrations of substitutional impurity. Calculation showed that the chosen interaction potential reproduces correctly the changes of the sign of the energy of mixing as a function of Cr concentration. When applied in Monte Carlo kinetic modelling the potential predicts correctly the immiscibility of initially chaotic Fe–Cr alloys as a function of Cr content. The Cowley short-range order parameter is determined that is used for quantitative estimation of the degree of ordering. A strong tendency towards ordering in Cr distribution is observed at low concentrations which is exhibited by negative values of short-range order parameters, in accordance with the experiment.

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BELENKII, A. Ya, and M. A. FRADKIN. "Local Electronic Structure and Short-Range Order in a Computer Simulated Amorphous Metal." International Journal of Modern Physics C 02, no. 01 (1991): 232–37. http://dx.doi.org/10.1142/s0129183191000238.

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The relationship between topological short-range order and a local electronic structure was analyzed in the computer model of an amorphous metal. The model, obtained by means of the original self-consistent cluster simulation procedure was studied with the use of Voronoi tesselation, the distribution of the atomic level stresses and the icosahedral order parameters. It was found that a marked correlation exists within 2 atomic parameter groups, one of which corresponds to the local dilatation and the other to the spherical symmetry distortion. The local density of electronic d-states (DOS) and the distribution of the electronic parameters was analyzed. The local electronic structure, calculated within the tight-binding approximation, appears to depend on the local atomic order by two-fold means: the interatomic distances decrease leads to the increase of the local bandwidth, and the icosahedral configuration distortion reduces the DOS at the Fermi level. The study of the local configurations stability shows, that the most stable configurations are the slightly distorted icosahedra.

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Jang, Hyun M., and Su-Chan Kim. "Pb()O3-type Perovskites: Part I. Pair-correlation Theory of Order-disorder Phase Transition." Journal of Materials Research 12, no. 8 (1997): 2117–26. http://dx.doi.org/10.1557/jmr.1997.0284.

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The limitation of the long-range order parameter and the necessity of the short-range order parameter for the thermodynamic description of Pb()O3-type perovskites are discussed. Based on the discussion, a statistical thermodynamic model that takes into account the configuration of the neighboring B-site ions (B′ and B″ cations) was developed. A pair-correlation approximation was used in the calculation of the configurational entropy and the long-range coulombic interaction energy between the nearest B-site ions. The theoretical calculations using Pb(Sc1/2Ta1/2)O3 (PST) and Pb(Sc1/2Nb1/2)O3 (PSN) systems indicate that the short-range order parameter persists over a wide range of temperatures examined (0–1800 K) and that there possibly occur consecutive long-range order-disorder transitions in the configuration of B-site cations. The possibility of the existence of short-range ordering above the long-range order-disorder transition temperature was also examined using the annealed PSN specimen as a typical example of Pb()O3-type perovskites.

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Radchenko, Taras M., and Valentin A. Tatarenko. "Statistical Thermodynamics and Kinetics of Long-Range Order in Metal-Doped Graphene." Solid State Phenomena 150 (January 2009): 43–72. http://dx.doi.org/10.4028/www.scientific.net/ssp.150.43.

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The statistical-thermodynamics and kinetics models of atomic ordering in a metal-doped graphene (binary two-dimensional planar graphene-type crystal lattice) at 1/8, 1/4, and 1/2 stoichiometries are proposed. Impossibility of (completely) atomic-ordered distribution at 1/6 and 1/3 stoichiometries is ascertained in a graphene-type crystal lattice (in case of a short-range interatomic interactions at least). If a graphene is doped by the short-range interacting metal atoms, the superstructures described only by a one LRO parameter are possible; and if it is doped by the long-range interacting metal atoms, the new superstructures with the two or three LRO parameters may appear as well. If stoichiometry is 1/4, the structure has a one long-range order (LRO) parameter is more thermodynamically favorable than those have one or two LRO parameters. It is established that kinetics curves of LRO parameters can be non-monotonic for structures where there are two or three LRO parameters (because graphene-type lattice contains two sublattices, and mixing energy is different for each of them). It is shown that the most ordered is structure with equal atomic fractions of carbon and metal atoms, while the least one is structure with a maximal difference of carbon and metal atoms. Kinetics results confirm statistical-thermodynamic ones: firstly, equilibrium values of LRO parameter coincide within the framework of both models, secondly, equilibrium (and instantaneous) value of LRO parameter in a nonstoichiometric binary graphene-type structure (where atomic fraction of a doping component deviates from the stoichiometry to the side of the higher concentrations) may be higher than it is in a stoichiometric one. The dominance of the same physical mechanisms of atomic ordering in both mixed nanosystems and macrosystems is assumed.

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Sharma, Atul Kumar. "Structural Properties of Ga-Zn Liquid Alloys at 750 K by Molecular Interaction Volume Model." International Journal of Innovative Research in Science and Engineering 11, no. 3 (2025): 45–52. https://doi.org/10.5281/zenodo.15235785.

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Abstract The Structural properties like concentration-concentration structure factor also known as concentration fluctuations and short-range order parameter of Ga-Zn liquid alloys at 750 K have been studied theoretically. The theoretical model employed is well known statistical mechanical model i.e. molecular interaction volume model (MIVM). The investigative expressions are utilized to explore the thermodynamic functions such as excess free energy of mixing, free energy of mixing and activity, and structural properties i.e. concentration fluctuations and short-range order parameter for Ga-Zn liquid alloys at 750 K. The theoretical data of thermodynamic functions and structural properties are found to be in well agreement with the corresponding experimental data available in the literature. The results show the segregating nature of Ga-Zn liquid alloys at 750 K. 

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Hussain, Md Mosarrat, Rajendra Prasad Chaudhary, Anadi Prasad Singh, Jagdhar Mandal, and Indu Sekhar Jha. "Theoretical Prediction of the Thermophysical Properties of FeSi Melts." Defect and Diffusion Forum 442 (May 16, 2025): 83–100. https://doi.org/10.4028/p-6e0ugx.

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The FeSi system is a compound forming alloy which exhibits the interesting behavior with respect to the composition. In present work, the thermophysical properties of FeSimelts at 1873 K have been explored on using four-parameter model which is based on Maclaurin infinite series. The analytical expressions for various thermodynamic and microscopic functions have been deduced using the standard thermodynamic relations. The model parameters are estimated using experimental data of activity coefficients and excess free energy of mixing for FeSi melts at 1873 K. For theoretical calculations of the thermophysical properties of FeSi liquid alloys at 1873 K, the same values of the model parameters are used in order to maintain the consistency. The composition dependence of theoretical data for Gibbs free energy of mixing and thermodynamic activities are in excellent agreement with the corresponding experimental data at 1873 K. On using the temperature dependence of model parameters, the enthalpy of mixing and entropy of mixing of FeSi molten alloys at 1873 K arecomputed. There is a well agreement between the theory and experiment. The theoretical values of concentration-concentration structural factor, known as concentration fluctuations in the long wavelength limit agree well with experimental data for FeSi system in molten state at 1873 K. The microscopic function such as short-range order parameter has also been computed as a function of concentration of FeSi melts at 1873 K. Again, the surface properties such as surface concentration and surface tension of FeSi molten alloys at the temperatures at 1823 K and 1873 Kare analyzed by Butler modelin the framework of four-parameter model. The theoretical values are compared with the data available in the literature at 1823 K which show well agreement. Again, the excess free energy of mixing, heat of mixing, concentration fluctuations and short-range order parameter are explored at 1823 K, 1873 K, 1923 K and 2073 K. Further, the transport properties like diffusivity ratio and viscosity of FeSi liquid alloys at 1823 K, 1873 K, 1923 K and 2073 Kare computed. For this, a simple statisticalmechanical modeli.eMoelwyn-Hughes model isemployed in the framework of four-parameter model. The theoretical data exhibit the qualitative agreement with the data available in the literature. The present study reveals that FeSi melt is an ordered system in the temperature range 1823-2073 K. The model parameters are temperature dependent. The concentration dependence of short-range order parameter and diffusivity ratio indicates that there is a likelihood of the existence of complex in FeSi liquid alloys. Keywords:Free energy of mixing; heat of mixing; concentration fluctuations; short-range order parameter, surface tension; viscosity

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13

Schönfeld, Bernd, Markus Engelke, and Andrei V. Ruban. "Order and Disorder in Ni-Pt Single Crystals." Solid State Phenomena 172-174 (June 2011): 593–601. http://dx.doi.org/10.4028/www.scientific.net/ssp.172-174.593.

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Single crystals of Ni-25.6 at.% Pt and Ni-87.8 at.% Pt were investigated by diffuse x-ray scattering for states of thermal equilibrium (923 K and 603 K, respectively). The separated short-range order scattering showed local maxima at 100 positions. Effective pair interaction parameters, as determined by the inverse Monte Carlo method, show a strong composition dependence of the nearest-neighbor interaction parameter. First-principles calculations are consistent with this finding and reveal a large contribution due to lattice strain. Based on values of the ordering energy, NiPt3with L12structure was considered as a plausible new intermetallic phase, with Monte Carlo simulations giving an order-disorder transition temperature of 650 K. A single crystal of Ni-75.2 at.% Pt, quenched from 1073 K and aged at 613 K, showed L12-type ordering, reaching a long-range order parameter of 0.50(4) after 800 h.

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14

Fishman, R. S. "Perturbative results for the short-range order parameter, specific heat, and resistivity of granular superconductors." Physical Review B 38, no. 7 (1988): 4437–47. http://dx.doi.org/10.1103/physrevb.38.4437.

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15

Kim, Su-Chan, and Hyun M. Jang. "Pb()O3-type Perovskites: Part II. Short-range Order Parameter as a Criterion of the Distinction Between Relaxor and Normal Ferroelectrics." Journal of Materials Research 12, no. 8 (1997): 2127–33. http://dx.doi.org/10.1557/jmr.1997.0285.

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A classification scheme of Pb()O3-type perovskites with respect to the B-site order parameters was proposed based on the theoretical calculation of the short-range order parameter (σ) using the pair-correlation model. The calculated order parameters predict that a Pb()O3-type perovskite without any charge difference between B′ and B″ cations [e.g., Pb(Zr1/2Ti1/2)O3 (PZT)] is represented by a completely disordered state with the absence of a finite coherence length. On the other hand, a Pb()O3-type perovskite system having different ionic charges is characterized either by the short-range ordering with a nanoscale coherence length or by the macroscopic long-range ordering, depending on the magnitude of ionic charge difference between B′ and B″ ions. The normal ferroelectricity in Pb()O3-type complex perovskites was then correlated either with a completely disordered state (σ = 0) or with a perfectly ordered state (σ = 0), whereas the relaxor behavior was attributed to the nanoscale short-range ordering (0 < σ < 1) in the configuration of the B-site cations.

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Biswajit, Ghatak, and Mandal Jagdhar. "Analysis of interionic potentials in chalcogenide crystals with sodium chloride structure." Journal of Indian Chemical Society Vol. 86, Dec 2009 (2009): 1271–79. https://doi.org/10.5281/zenodo.5823832.

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University Department of Physics, T. M. Bhagalpur University, Bhagalpur-812 007, Bihar, India Manuscript received 24 September 2008, revised 3 June 2009, accepted 3 June 2009 Values of cohesive energy, atomization energy, force constant, IR absorption frequency, Debye temperature, Grüneisen parameter, Anderson-Griineisen parameter and Moelwyn-Hughes parameter for 45 chalcogenide crystals of NaCI-structure are reported here. These parameters have been obtained by using the Born-Mayer and Varshini-Shukla interionic short-range repulsive interactions. Calculations have also been performed for the computation of first order volume dependence of Grüneisen parameter commonly known as second Griineisen parameter using expressions of higher order derivatives of interaction potential within the frame work of Dugdale and MacDonald theory. The high pressure behaviour of these crystals have also been studied.

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Singh, Anadi Prasad, Rajendra Prasad Chaudhary, Md Mosarrat Hussain, Jagdhar Mandal, and Indu Sekhar Jha. "Theoretical Study of the Stability of CdSn Liquid Alloy at Different Temperatures." Diffusion Foundations and Materials Applications 37 (December 24, 2024): 37–51. https://doi.org/10.4028/p-efgqf5.

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The quasi-lattice theory (QLT) is utilized for the prediction of the temperature and concentration dependence of the thermodynamic properties of the molten CdSn alloys. At first, the analytical expressions are employed to reckon the excess Gibbs free energy of mixing, Gibbs free energy of mixing, activity, enthalpy of mixing and entropy of mixing as well as concentration fluctuations, short range-order parameter and excess stability function ofCdSn melts at 773 K. For this, the model parameters i.e. size ratio and order energy parameter are assessed using the experimental data of the free energy of mixing for CdSnmelts at 773 K. The theoretical values of the thermodynamic functions are in well harmony with the interrelated experimental values. The theoretical values of the structure function like concentration fluctuations are in unison with the experimental values for molten CdSn system at 773 K. Again, the optimization procedure is applied to explore the excess Gibbs free energy of mixing, activity, concentration fluctuations, short-range order parameter and excess stability function at different temperatures for CdSnmelts. The present study discloses that the stability as well as the segregating nature of CdSnmelts decrease with the elevation of the temperature from 773 K to 1123 K. Further, the temperature dependency of the excess stability function reveals that there is a probability of transition from segregating character to the ordering character of CdSn melts near 1162 K. Keywords: Gibbs free energy of mixing; entropy of mixing; concentration fluctuations; short-range order parameter; excess stability function

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Kravets, V. G., and L. V. Poperenko. "Influence of the short-range order parameter on the optical properties of amorphous nickel-phosphorus alloy." Russian Physics Journal 40, no. 5 (1997): 435–39. http://dx.doi.org/10.1007/bf02508772.

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Biswajit, Ghatak, and Mandal Jagdhar. "Theoretical study of crystalline state properties of heavy metal halide with different structures." Journal of Indian Chemical Society Vol. 86, Jan 2009 (2009): 32–37. https://doi.org/10.5281/zenodo.5807058.

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University Department of Physics, T. M. Bhagalpur University, Bhagalpur-812 007, Bihar, India Manuscript received 11 December 2007, revised 4 September 2008, accepted 9 September 2008 The crystalline state properties such as cohesive energy, atomization energy, force constant, IR absorption frequency, Debye temperature, Grüneisen parameter, Anderson Grüneisen parameter, Moelwyn-Hughes parameter of heavy metal halide are reported here. These parameters have been obtained by using the Born-Mayer, Hellmann, VarshiniShukla and Ali-Hasan interionic short-range repulsive interactions. Calculations are also performed for the computation of first order volume dependence of Grüneisen parameter commonly known as second Grüneisen parameter using expressions of higher order derivatives of interaction potential within the framework of Dugdale and MacDonald theory. The high pressure behaviour of these crystals has also been studied.

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20

Ahmad, Shayista, M. P. Sah, R. P. Chaudhary, I. S. Jha, and J. Mandal. "Theoretical assessment for the mixing properties of AlMg liquid alloys at 1073K." Journal of Physics: Conference Series 2070, no. 1 (2021): 012074. http://dx.doi.org/10.1088/1742-6596/2070/1/012074.

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Abstract The alloying behavior of AlMg alloy in the liquid form at 1073 K has been theoretically investigated in the framework of four-parameter model which is based on Maclaurin series. The analytical expressions for thermodynamic functions such as excess free mixing energy, free mixing energy, enthalpy of mixing and entropy of mixing and microscopic functions such as concentration fluctuations at the long wavelength limit and Warren-Cowley chemical short range order parameter have been derived. These expressions have been used to compute the excess Gibbs free energy of mixing, Gibbs free energy of mixing, activity, enthalpy(heat) of mixing, excess entropy of mixing, entropy of mixing, concentration fluctuations in long wavelength limit and Warren-Cowley short range order parameters of AlMg liquid alloys at 1073 K. The investigation shows the excellent concurrence between the experimental and theoretical measurements of the mixing properties of AlMg liquid alloys at 1073 K. Interaction parameters of energy depends on temperature.

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Biswajit, Ghatak, and Mandai Jagdhar. "Computation of crystalline state properties of chalcogenide crystals with antifluorite structure." Journal of Indian Chemical Society Vol. 88, Jul 2011 (2011): 977–82. https://doi.org/10.5281/zenodo.5785098.

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University Department of Physics, T. M. Bhagalpur University, Bhagalpur-812 007, Bihar, India E-mail : biswajit.ghatak@rediffmail.com Manuscript received 31 December 2008, accepted 30 December 2010 The crystalline state properties such as of cohesive energy, atomization energy, force constant, IR absorption frequency, Debye temperature, Griineisen parameter, Anderson-Griineisen parameter and Moelwyn-Hughes parameter for 14 chalcogenlde crystals of antifiuorite are reported here. These parameters have been obtained by using the Born-Mayer and Varshni-Shukla interionic short-range repulsive interactions. Calculations are also performed for the computation of first order volume dependence of Griineisen parameter commonly known as second Griineisen parameter using expressions of higher order derivatives of interaction potential within the frame work of Dugdale and Macdonald theory. The high pressure behaviour of these crystals have also been studied. The results obtained here may add a little to the physics and chemistry of these crystals.

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XIANG, YUANTAO, and A. JAMNIK. "STRINGENT VERIFICATION OF THIRD ORDER + SECOND ORDER PERTURBATION DENSITY FUNCTION THEORY: BASED ON SHORT-RANGE SQUARE WELL POTENTIAL." International Journal of Modern Physics B 24, no. 32 (2010): 6291–306. http://dx.doi.org/10.1142/s021797921005764x.

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A recently proposed third order + second order perturbation density functional theory (DFT) approach is made self-contained by using a virial pressure from the Ornstein–Zernike integral equation theory as input to determine the numerical value of an associated physical parameter. An exacting examination is formulated by applying the self-contained perturbation DFT approach to a short-range square well fluid of low temperatures subject to various external fields and comparing the theoretical results for density profiles to the corresponding grand canonical ensemble Monte Carlo simulation results. The comparison seems favorable for the third order + second order perturbation DFT approach as a self-contained and accurate predictive approach. It is surprisingly found that this self-contained third order + second order perturbation DFT approach is displayed outstandingly even if a deep SW perturbation term is being accounted for by a second order perturbation expansion. A discussion is presented about potential opportunity for this perturbation scheme.

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Dominicis, C. De, I. Kondor, and T. Temesvari. "Short-range corrections to the order parameter of the Ising spin glass above the upper critical dimension." Journal of Physics A: Mathematical and General 24, no. 6 (1991): L301—L308. http://dx.doi.org/10.1088/0305-4470/24/6/009.

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Kondor, I., C. De Dominics, and T. Temesvári. "Short range corrections to the order parameter and to the excitation spectrum of the Ising spin glass." Physica A: Statistical Mechanics and its Applications 185, no. 1-4 (1992): 295–304. http://dx.doi.org/10.1016/0378-4371(92)90468-6.

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25

Manceau, Alain, Matthew A. Marcus, S. Grangeon, et al. "Short-range and long-range order of phyllomanganate nanoparticles determined using high-energy X-ray scattering." Journal of Applied Crystallography 46, no. 1 (2013): 193–209. http://dx.doi.org/10.1107/s0021889812047917.

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High-energy X-ray scattering (HEXS) is used to explore the pH-dependent structure of randomly stacked manganese oxide nanosheets of nominal formula δ-MnO2. Data are simulated in real space by pair distribution function (PDF) analysis and in reciprocal space by both the Bragg-rod method and the Debye equation in order to maximize the information gained from the total scattering measurements. The essential new features of this triple-analysis approach are (1) the use of a two-dimensional supercell in PDF modeling to describe local distortions around Mn layer vacancies, (2) the implementation in Bragg-rod calculations of a lognormal crystal size distribution in the layer plane and an empirical function for the effect of strain, and (3) the incorporation into the model used with the Debye equation of an explicit elastic deformation of the two-dimensional nanocrystals. The PDF analysis reveals steady migration at acidic pH of the Mn atoms from layer to interlayer sites, either above or below the Mn layer vacancies, and important displacement of the remaining in-layer Mn atoms toward vacancies. The increased density of the vacancy–interlayer Mn pairs at low pH causes their mutual repulsion and results in short-range ordering. The layer microstructure, responsible for the long-range lateral disorder, is modeled with spherically and cylindrically bent crystallites having volume-averaged radii of 20–40 Å. Thebunit-cell parameter from the hexagonal layer has different values in PDF, Bragg-rod and Debye equation modeling, because of the use of different weighting contributions from long-range and short-range distances in each method. The PDFbparameter is in effect a measure of the average inlayer Mn...Mn distance and consistently deviates from the average structure value determined by the Bragg-rod method by 0.02 Å at low pH, as a result of the local relaxation induced by vacancies. The layer curvature increases the Bragg-rod value by 0.01–0.02 Å with the cylindrical model and as much as 0.04–0.05 Å with the spherical model. Therefore, in principle, the diffraction alone can unambiguously determine with good accuracy only a volume-averaged apparent layer dimension of the manganese oxide nanosheets. Thebparameter is model dependent and has no single straightforward interpretation, so comparison ofbbetween different samples only makes sense if done in the context of a single specified model.

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J., Mandai, and Ghatak B. "A comparative study of crystalline state properties of alkali halides using the three standard potential models." Journal of Indian Chemical Society Vol. 84, Sep 2007 (2007): 942–44. https://doi.org/10.5281/zenodo.5827373.

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University Department of Physics, T. M. Bhagalpur University, Bhagalpur-812 007, Bihar, India Manuscript received 15 January 2007, revised 1 June 2007, accepted 11 July 2007 Interionic short-range repulsive potential models due to Born-Mayer, Hellmann and Ali-Hasan have been used to estimate the crystalline state properties such as cohesive energy, atomization energy, Gruneisen parameter, Andersen-Gruneisen parameter, Moelwyn-Hughes parameter and first order volume dependence of Gruneisen parameter commonly known as second order Gruneisen parameter of alkali halides of NaCI structure.

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Ruppersberg, H. "Chemical short-range order parameter and ordering enthalpy in binary hard-sphere systems with unequal hard-sphere diameters." Journal of Non-Crystalline Solids 106, no. 1-3 (1988): 89–91. http://dx.doi.org/10.1016/0022-3093(88)90235-9.

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Lamparter, P., and S. Steeb. "Structure of Metallic Glasses: Experiments and Models." Zeitschrift für Naturforschung A 51, no. 9 (1996): 983–90. http://dx.doi.org/10.1515/zna-1996-0902.

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Abstract The topological and the chemical short range order in metallic glasses is discussed by means of representative examples from the systems Ni-P, Ni-B, Nb-Ni, and Dy-Ni. The characterization of the chemical short range order, e.g. in terms of a short range order parameter, depends on the definition of an appropriate hypothetic statistical reference system. The consideration of the size effect is essential. Some structural features of metallic glasses point to relationships with the related individual crystalline phases, whereas other features show that the different types of metallic glasses have certain construction principles in common. Small angle scattering with hydrogenated metallic glasses suggests the presence of extended two-dimensional structures. Reverse Monte Carlo models reveal rather broad distributions of the local structural properties and show that metallic glasses are not built as assemblies of defined structural units.

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Yim, C. T., and D. F. R. Gilson. "Orientation of some disk-shaped solutes in nematic liquid crystals." Canadian Journal of Chemistry 66, no. 7 (1988): 1749–51. http://dx.doi.org/10.1139/v88-281.

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The solute orientation parameters for benzene, trichloro-, and tribromobenzene have been measured, as functions of temperature, in the nematic solvents EBBA and ZLI-1132. The potential functions for orientation were derived for the model based on short and long-range contributions to the potential, with the former dependent on either a function of molecular shape or of molecular volume. There is reasonable agreement between calculated and experimental solute order parameters in both cases, and the difference in solute order parameter in the two solvents arises mainly from the difference in solvent electric field gradient.

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Zhao, S. Z., J. H. Li, and B. X. Liu. "Local structure of the Zr–Al metallic glasses studied by proposed n-body potential through molecular dynamics simulation." Journal of Materials Research 25, no. 9 (2010): 1679–88. http://dx.doi.org/10.1557/jmr.2010.0225.

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An n-body potential is first constructed for the Zr–Al system and proven to be realistic by reproducing a number of important properties of the system. Applying the constructed potential, molecular dynamics simulations, chemical short-range order (CSRO) calculation, and Honeycutt and Anderson (HA) pair analysis are carried out to study the Zr–Al metallic glasses. It is found that for the binary Zr–Al system, metallic glasses are energetically favored to be formed within composition range of 35–75 at.% Al. The calculation shows that the CSRO parameter is negative and could be up to −0.17, remarkably indicating that there exists a chemical short-range order in the Zr–Al metallic glasses. The HA pair analysis also reveals that there are diverse short-range packing units in the Zr–Al metallic glasses, in which icosahedra and icosahedra/face-centered cubic (fcc)-defect structures are predominant.

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Furutani, Katsushi, Hiroshi Tachi, and Mitsuru Saito. "Linear Measurement and Training Device for Leg Evaluation." International Journal of Automation Technology 3, no. 3 (2009): 298–303. http://dx.doi.org/10.20965/ijat.2009.p0298.

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The measuring device we developed to evaluate the leg and use in physical training is driven by a linear motor using impedance or proportional-integral control. The leg is considered a second-order system in the short range. For a leg flexed at a constant speed, we calculated parameters from measured force, displacement, and acceleration and measured parameter transitions in exercise. While the damping coefficient remained almost flat during exercise, the spring constant changed.

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32

Rendell, J. C. T., D. S. Zimmerman, A. J. van der Est, and E. E. Burnell. "Orientational order of 1,3-dichloro-2-ethenylbenzene in liquid-crystal solvents." Canadian Journal of Chemistry 75, no. 8 (1997): 1156–61. http://dx.doi.org/10.1139/v97-138.

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The order parameter matrices of a molecule that has no symmetry, 1,3-dichloro-2-ethenylbenzene, dissolved in two different nematic liquid-crystal solvents are analyzed in terms of various models for the intermolecular mean-field potential. In a mixture of liquid crystals for which the interaction between the molecular quadrupole moment tensor and the average electric field gradient of the nematic solvent has been minimized, the orientational order is best described by models for the short-range anisotropic potential. The most successful potentials are written in terms of anisotropic interactions between the solute surface and the liquid-crystal mean field. This represents a strong test of such models because they simultaneously fit the five independent orientational parameters obtained from the same solute, thus removing the problems associated with comparing results among different solutes in either the same or a different sample tube. Keywords: liquid crystals, intermolecular forces, order parameters, anisotropic.

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33

Heckele, M., R. Bellissent, A. Brunseh, P. Lamparter, and S. Steeb. "Influence of Hydrogen on the Structure of Amorphous Sputtered Fe-Co-Tb Films by Means of Wide- and Small Angle Neutron Scattering." Zeitschrift für Naturforschung A 46, no. 12 (1991): 1015–20. http://dx.doi.org/10.1515/zna-1991-1203.

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Abstract Sputtered amorphous Fe-Co Tb-films with perpendicular and in-plane magnetic anisotropy were investigated by wide- and small angle neutron scattering. By combination with X-ray data the maxima in the pair correlation function could be attributed to the individual atomic pairs. Thus also partial coordination numbers and a short range order parameter could be determined. Wide angle diffraction revealed that the film with magnetic in-plane anisotropy contained 13 atomic percent hydrogen. The hydrogen incorporation causes substantial changes in the short range order, associated with enhanced formation of Tb-rich clusters, and the in-plane anisotropy. The clustering effect was confirmed by results from small angle scattering with polarized neutrons

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34

Shirakami, Tatsuya, Michihiro Mitsukawa, Takahito Imai, and Kazuyori Urabe. "A New Method of Determining Short-Range Order Parameter in Relaxor Pb(Ni1/3Nb2/3)O3 by Magnetic Susceptibility Measurement." Japanese Journal of Applied Physics 39, Part 2, No. 7A (2000): L678—L680. http://dx.doi.org/10.1143/jjap.39.l678.

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LI, Z. B., Y. CHEN, and S. H. GUO. "SHORT-TIME CRITICAL BEHAVIOR OF THE GINZBURG–LANDAU MODEL WITH QUENCHED DISORDER." Modern Physics Letters B 15, no. 02 (2001): 43–55. http://dx.doi.org/10.1142/s0217984901001409.

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The theoretic renormalization-group approach is applied to the study of short-time dynamics of the d-dimensional n-component spin systems with long-range interactions r-(d+σ) and quenched disorder which has long-range correlations r-(d-ρ). Asymptotic scaling laws are obtained in a frame of double expansions in ∊=2σ-d and ρ with ρ of the order ∊. The static exponents are obtained exactly to all the order. The initial slip exponents θ′ for the order parameter and θ for the response function, as well as the dynamic exponent z, are calculated upto the first order in ∊. In d=2σ, in contrast to the unique logarithmic decay in the long-time regime which does not depend on σ, ρ, n and the disorder, we find rich scaling structures including logarithmic and exponential-logarithmic scalings in the short-time regime. Non-universal critical scalings of Ising systems are also discussed for d=2σ.

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36

Shamseldin, Mohamed A., Mahmoud Salah, Abdel Ghany Mohamed, and M. A. Abdel Ghany. "A COVID-19 Based on Fractional Order Integral-Tilt Derivative Controller for Nonlinear Servomechanism Model." International Journal of Electrical Engineering and Computer Science 5 (November 6, 2023): 175–82. http://dx.doi.org/10.37394/232027.2023.5.19.

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In this research, a new one-axis servomechanism investigation is presented, taking into account parameter fluctuation and system uncertainty. Additionally, a novel method for very effective TID control was created to accurately monitor a chosen profile. A comparative study between the suggested control method and the well-known controllers (PID and Nonlinear PID) is also included. The COVID-19 optimization technique was used to discover the best control parameters. Through the online simulation, the servomechanism system's settings were modified at random within a predetermined range. As nonlinearity resources (friction, backlash, environmental influences), these parameters fluctuate and contribute to system uncertainty. It had been completed and looked at to compare the linear and nonlinear models. The results demonstrate that the suggested controller is capable of tracking the number of operational points with high accuracy, a short rising time, and little overrun.

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37

Kuschke, W. M., P. Lamparter, and S. Steeb. "Local Structure of the Amorphous Ni25Zr75-Alloy by Using the Isotope-Substitution Neutron Diffraction Method." Zeitschrift für Naturforschung A 46, no. 11 (1991): 951–54. http://dx.doi.org/10.1515/zna-1991-1105.

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AbstractUsing neutron diffraction as well as the method of isotopic substitution the partial Bhatia-Thornton as well as the partial Faber-Ziman structure factors of amorphous Ni25Zr75 were determined. A compound forming tendency was found. The atomic distances, partial coordination numbers, and the chemical short range order parameter are evaluated.

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38

Buntar’, V. A., V. N. Grigor’ev, O. I. Kirichek, Yu Z. Kovdrya, and Yu P. Monarkha. "Liquid phase of surface electrons on helium." Soviet Journal of Low Temperature Physics 12, no. 8 (1986): 450–52. https://doi.org/10.1063/10.0031553.

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When the parameter Γ=e2π1/2ns1/2/kt&gt;47 the lifetime τ of surface electrons on liquid helium is much longer when the applied electric field is smaller than its equilibrium value. The increase is due to the appearance of short-range order characteristic of the liquid state.

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Born, R., D. Hohlwein, and G. Eckold. "Orientational disorder in ammonium chloride: elastic diffuse neutron scattering with a new technique." Journal of Applied Crystallography 22, no. 6 (1989): 613–19. http://dx.doi.org/10.1107/s002188988900631x.

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Elastic diffuse neutron scattering intensity due to orientational disorder in ND4Cl at room temperature, space group Pm3m, is studied with a single crystal. By a novel `vertical' energy analysis on the one hand and the `flat-cone' technique on the other, the intensity is obtained in a large three-dimensional region of reciprocal space in a reasonable time. The data are analysed with short-range-order and interaction-potential parameters. The two parameter sets are consistent. Local chlorine displacements of 0.16 Å, along 〈111〉 directions are determined.

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Adhikari, D., B. P. Singh, and I. S. Jha. "Concentration Fluctuation in Long Wavelength Limit in Liquid Magnesium Alloy." Himalayan Physics 2 (July 31, 2011): 47–49. http://dx.doi.org/10.3126/hj.v2i2.5211.

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The microscopic structure of MgSn liquid alloy at 1073K has been studied by using regular associated solution model. For this we have calculated the concentration fluctuation in long wave length limit [SCC(0)] and chemical short range order parameter (α1) of liquid MgSn alloy at 1073 K.Keywords: Binary Alloy; Complex; Chemical order; Microscopic FunctionThe Himalayan Physics Vol.2, No.2, May, 2011Page: 47-49Uploaded Date: 1 August, 2011

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A., K. Jha, Kumari V., D. Yadav R., and K. Mishra A. "Thermodynamic and surface properties of binary liquid alloys." Journal of Indian Chemical Society Vol. 87, Jul 2010 (2010): 803–10. https://doi.org/10.5281/zenodo.5792541.

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Department of Chemistry, Department of Physics, Principal G. B. College, Naugachia-853 204, Bhagalpur, Bihar, India E-mail : ashokjha39@gmail.com Manuscript received 26 October 2009, accepted 31 December 2009 The first order Interaction parameters using Maclaurin infinite series have been used to Investigate thermodynamic and surface properties of binary liquid alloys. The evaluated excess free energy of mixing or binary liquid alloys and activity coefficients of Its constituent atoms are In agreement with the experiment. The study of concentration-concentration fluctuations at long wave length limit (Scc(0)) and chemical short range order parameter (a1) reveals that MgZn liquid binary alloy Is a complex forming alloy and II is more ordered towards Zn-rich end than Mg-rich end. The surface tension of Zn is lowered with the addition of Mg. Mg atoms are more active at the surface than that in the bulk throughout the whole concentration range where as It is up to 40%or concentration or Zn in the case or Zn atoms. Mg atoms segregate to the surface In MgZn liquid binary alloy but the degree of segregation is low.

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Mubassira, Subah, Wu-Rong Jian, and Shuozhi Xu. "Effects of Chemical Short-Range Order and Temperature on Basic Structure Parameters and Stacking Fault Energies in Multi-Principal Element Alloys." Modelling 5, no. 1 (2024): 352–66. http://dx.doi.org/10.3390/modelling5010019.

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In the realm of advanced material science, multi-principal element alloys (MPEAs) have emerged as a focal point due to their exceptional mechanical properties and adaptability for high-performance applications. This study embarks on an extensive investigation of four MPEAs—CoCrNi, MoNbTa, HfNbTaTiZr, and HfMoNbTaTi—alongside key pure metals (Mo, Nb, Ta, Ni) to unveil their structural and mechanical characteristics. Utilizing a blend of molecular statics and hybrid molecular dynamics/Monte Carlo simulations, the research delves into the impact of chemical short-range order (CSRO) and thermal effects on the fundamental structural parameters and stacking fault energies in these alloys. The study systematically analyzes quantities such as lattice parameters, elastic constants (C11, C12, and C44), and generalized stacking fault energies (GSFEs) across two distinct structures: random and CSRO. These properties are then evaluated at diverse temperatures (0, 300, 600, 900, 1200 K), offering a comprehensive understanding of temperature’s influence on material behavior. For CSRO, CoCrNi was annealed at 350 K and MoNbTa at 300 K, while both HfMoNbTaTi and HfNbTaTiZr were annealed at 300 K, 600 K, and 900 K, respectively. The results indicate that the lattice parameter increases with temperature, reflecting typical thermal expansion behavior. In contrast, both elastic constants and GSFE decrease with rising temperature, suggesting a reduction in resistance to stability and dislocation motion as thermal agitation intensifies. Notably, MPEAs with CSRO structures exhibit higher stiffness and GSFEs compared to their randomly structured counterparts, demonstrating the significant role of atomic ordering in enhancing material strength.

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Повзнер, А. А., А. Г. Волков, Т. А. Ноговицына та C. А. Бессонов. "Индуцированные флуктуациями фазовые переходы и скирмионы в сильно коррелированных Fe-=SUB=-1-x-=/SUB=-Co-=SUB=-x-=/SUB=-Si с нарушенной кристаллической структурой типа В20". Физика твердого тела 63, № 3 (2021): 315. http://dx.doi.org/10.21883/ftt.2021.03.50579.227.

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Concentration and temperature transitions in strongly correlated Fe1-хCoxSi alloys with the Dzyaloshinsky-Moriyya (DM) interaction are considered within the framework of the spin-fluctuation theory and taking into account the results of LDA+U+SO calculations of the density of electronic states. It is shown that order-order concentration transitions with a change in the sign of the left-handed spin chirality (at x <0.2) to right-handed (at 0.2≤x<0.65), and again to left-handed, are associated with a change in the sign of the intermode interaction parameter. At the same time, it was indicated that in the region of compositions Fe1-хCoxSi 0.2≤x<0.65, temperature-prolonged first-order phase transitions appear, accompanied by the appearance of an intermediate temperature region of spin short-range order with uncompensated local magnetization and DM interaction. In an external magnetic field in this temperature range at 0.2<x<0.65, skyrmion microstructures appear. At x=0.65, the intermode interaction parameter becomes zero, and the long-range order becomes ferromagnetic (since the experiment implies compensation for the DM interaction). Instead of a prolonged first-order transition, a second-order temperature transition occurs at х=0.65. The constructed (h-T) diagrams of the magnetic states of Fe1-хCoxSi agree with the experiment.

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Koirala, RP, IS Jha, BP Singh, and D. Adhikari. "Structural study of liquid Sn-Tl alloys." BIBECHANA 11 (May 8, 2014): 46–52. http://dx.doi.org/10.3126/bibechana.v11i0.10379.

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The concentration fluctuations in long wavelength limit, Scc(0) and the Warren-Cowley short range order parameter (α1) are important microscopic functions which provide valuable information about the local arrangements of the constituent atoms in the alloy melts. In order to investigate the nature of atomic ordering in Sn-Tl alloy in the molten state at 723K, we have computed these functions using theoretical models. The models satisfactorily explain the small asymmetry observed in the experimental data of free energy of mixing of the alloy. The comparative study further reveals that the energy interaction parameters are temperature dependent and the Sn-Tl alloy is weakly interacting segregating system. DOI: http://dx.doi.org/10.3126/bibechana.v11i0.10379 BIBECHANA 11(1) (2014) 46-52

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L'vov, Victor A., Anna Kosogor, Outi Söderberg, and Simo Pekka Hannula. "The Symmetry-Conforming Theory of Martensite Aging." Materials Science Forum 635 (December 2009): 13–19. http://dx.doi.org/10.4028/www.scientific.net/msf.635.13.

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The Landau theory has been developed for the description of martensite aging. The characteristic features of the theory are: i) the multicomponent non-scalar character of the order parameter describing the slow reconfiguration of lattice defects after martensitic transformation (MT); ii) the complete agreement with Symmetry-Conforming Short-Range-Order principle formulated by X. Ren and K. Otsuka; iii) the applicability to the different MT-s and various defects related to aging phenomena. The physical values interpreted as the components of internal stress, which stabilizes certain variant of martensitic phase, have been composed of the components of slow non-scalar order parameter. An applicability of the developed theory to the description of influence of aging on the MT temperature and yield stress was demonstrated.

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Bhandari, I. B., N. Panthi, S. Gaire, and Ishwar Koirala. "Effect of temperature on mixing behavior and stability of liquid Al-Fe alloys." Journal of Physics: Conference Series 2070, no. 1 (2021): 012025. http://dx.doi.org/10.1088/1742-6596/2070/1/012025.

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Abstract A theoretical model based on the assumption of compound formation in binary liquid alloy has been used to investigate the thermodynamic properties (free energy of mixing, enthalpy of mixing and entropy of mixing), microscopic properties (concentration fluctuation in long wavelength limit and chemical short range order parameter), surface properties (surface tension and surface composition) and dynamic properties ( viscosity and diffusion coefficient). All the properties of Al2Fe binary melt have been measured using the same energy parameters configured for experimental values of free energy of mixing. The energy parameters are detected as independent of concentration, but depend on temperature. The findings are well consistent with the experimental standards.

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Prasad, L. C., and R. N. Singh. "Quasi-Chemical Model for Liquid Li-Cd Alloys." Zeitschrift für Naturforschung A 44, no. 6 (1989): 529–32. http://dx.doi.org/10.1515/zna-1989-0607.

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The quasi-chemical model based on pairwise interactions is used to study the concentration dependent thermodynamic properties of Li-Cd liquid alloys. Special attention is given to the concentration-concentration correlation function in the long wavelength limit [Scc(0)] and the chemical short-range order parameter (CSRO). The activity, free energy of mixing, Scc(0) and CSRO are computed as functions of temperature and concentration.

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Shrestha, G. K., I. S. Jha, and B. K. Singh. "Theoretical investigations on temperature dependence of thermodynamic properties and concentration fluctuations of In-Tl binary liquid alloys by optimization method." BIBECHANA 15 (December 19, 2017): 11–23. http://dx.doi.org/10.3126/bibechana.v15i0.18470.

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The thermodynamic properties, i.e. free energy of mixing (GM), heat of mixing (HM), entropy of mixing (SM) and activity (ai) of the component i (i , and structural property i.e. concentration fluctuations in long wave-length limit [Scc(0)] of In-Tl binary liquid alloy at a specified temperature have been investigated in the framework of quasi-lattice model on assuming the coupled effect of size ratio and entropic (or energetic) as well as enthalpic effect. These properties of In-Tl liquid alloy at 723 K have been computed theoretically by estimating the best fit value of order energy parameter (W) and size ratio () over the entire range of concentration in order to match their experimental values. The best fit value of W at 723 K has been used to determine the values of W at different temperatures with the help of temperature derivative of W which are then used for the optimization procedure in order to calculate the corresponding values of excess free energy of mixing, partial excess free energy of mixing and activity of the components involved in the alloy at different temperatures. These parameters have been used to investigate the concentration fluctuations in long wavelength limit {Scc(0)} of In-Tl binary liquid alloy at different temperatures over the entire range of concentration which have been used to predict the various other structural properties like excess stability function (EXS), diffusion coefficient ratio (Dm/Did), short range order parameter (α1) at different temperatures.BIBECHANA 15 (2018) 11-23

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Koirala, RP, BP Singh, IS Jha, and D. Adhikari. "Energetics and local order in In-based liquid alloys." BIBECHANA 13 (December 3, 2015): 60–71. http://dx.doi.org/10.3126/bibechana.v13i0.13359.

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A comparative study has been carried out to understand the concentration dependence of thermodynamic properties such as, free energy of mixing, heat of mixing, entropy of mixing, activity and microscopic properties, such as concentration fluctuation in long wavelength limit and Warren-Cowley short range order parameter of In-based three liquid alloys (In-Pb , In-Tl and In-Zn) on the basis of self-association model. The analysis reveals that self-association model successfully explains the observed properties of the liquid alloys. Positive deviation of the thermodynamic properties of the alloys from the Raoultian solution behaviour indicates that the alloys are weakly segregating in nature. The comparative assessment of the interaction energy and the microscopic properties suggests that the degree of segregation is greatest in In-Zn alloy and comparable in In-Pb and In-Tl alloys.BIBECHANA 13 (2016) 60-71

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Lee, T. A., A. Navrotsky, and I. Molodetsky. "Enthalpy of formation of cubic yttria-stabilized zirconia." Journal of Materials Research 18, no. 4 (2003): 908–18. http://dx.doi.org/10.1557/jmr.2003.0125.

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Oxide melt solution calorimetric measurements were made to determine the enthalpy of formation of cubic-yttria-stabilized zirconia (c-YSZ) with respect to the oxides m-ZrO2 and C-type YO1.5. The enthalpy of formation can be fit either by a quadratic equation or by two straight line segments about the minimum near x = 0.40. The quadratic fit gives a strongly negative interaction parameter, Ω=-93.7 ± 12.0 kJ/mol, but does not imply regular solution behavior because of extensive short-range order. In this fit, the enthalpy of transition of m-ZrO2 to c-ZrO2, 9.7 ± 1.1 kJ/mol, is in reasonable agreement with earlier estimates and that of C-type to cubic fluorite YO1.5, 24.3 ±14.4 kJ/mol, is consistent with an essentially random distribution of oxide ions and anion vacancies in the high-temperature fluorite phase. The two straight-line segments give 6.1 ± 0.6 kJ/mol and 5.5 ± 2.5 kJ/mol for these transitions, respectively. The latter value would imply strong short-range order in cubic fluorite YO1.5. Clearly more complex solution thermodynamic descriptions need to be developed. The enthalpy of transition from the disordered c-YSZ phase to the ordered δ-phase at 25 °C was also measured and was 0.4 ± 1.6 kJ/mol. No energetic difference between the disordered c-YSZ phase and the ordered δ-phase underscores the importance of short-range order in c-YSZ. Enthalpy data were combined with Gibbs free energy data to calculate entropies of mixing. Using the quadratic fit, negative excess entropy of mixing in the cubic solid solution, relative to a system with maximum randomness on cation and anion sublattices, was found and was another indication of extensive short-range order in c-YSZ.

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Journal articles on the topic 'Short-range order parameter'

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