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Journal articles on the topic 'Anharmonicitées'

Author: Grafiati

Published: 14 December 2024

Last updated: 31 July 2025

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1

Singh, Hempal, Anu Singh, Vinod Ashokan, and B. D. Indu B. D. Indu. "Signature of Anharmonicities in High Temperature Superconductors." Indian Journal of Applied Research 3, no. 4 (2011): 35–38. http://dx.doi.org/10.15373/2249555x/apr2013/134.

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2

Wu, Junjun, Lu Gem Gao, Wei Ren, and Donald G. Truhlar. "Anharmonic kinetics of the cyclopentane reaction with hydroxyl radical." Chemical Science 11, no. 9 (2020): 2511–23. http://dx.doi.org/10.1039/c9sc05632g.

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3

Gastegger, Michael, Jörg Behler, and Philipp Marquetand. "Machine learning molecular dynamics for the simulation of infrared spectra." Chemical Science 8, no. 10 (2017): 6924–35. http://dx.doi.org/10.1039/c7sc02267k.

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4

Kolesov, Egor A., Mikhail S. Tivanov, Olga V. Korolik, et al. "Phonon anharmonicities in supported graphene." Carbon 141 (January 2019): 190–97. http://dx.doi.org/10.1016/j.carbon.2018.09.020.

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5

INDU, B. D. "THEORY OF LATTICE SPECIFIC HEAT OF AN ISOTOPICALLY DISORDERED ANHARMONIC CRYSTAL." International Journal of Modern Physics B 04, no. 07n08 (1990): 1379–93. http://dx.doi.org/10.1142/s021797929000067x.

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Expressions are obtained for the phonon density of states (DOS), lattice energy and lattice heat capacity (LHC) of an isotopically disordered anharmonic crystal. The cubic and quartic anharmonicities are taken into account besides both the force constant changes and mass difference caused by the substitutional impurities. The method of double time thermal Green’s Function (GF) is used in the development. It is shown that in the low concentration limit the LHC depends on mass and force constant changes, cubic and quartic anharmonicities and impurity-anharmonicity interactions. At low temperatur

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6

Gupta, Anushri, Sanjeev K. Verma, Anita Kumari, and B. D. Indu. "Generalized phonon density of states of La2−xSrxCuO4 cuprate superconductor." International Journal of Modern Physics B 33, no. 28 (2019): 1950328. http://dx.doi.org/10.1142/s0217979219503284.

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Many body quantum dynamics of phonons is steadily developed by considering the various effects of anharmonicities, defects (consider as doping or impurity concentration) and electron–phonon interactions in model Hamiltonian (instead of BCS Hamiltonian) for a high-temperature superconductor (HTS). This enables to obtain the expressions for the renormalized phonon spectrum, the renormalized phonon density of states (RPDOS). The RPDOS can be resolved into diagonal and nondiagonal parts where the nondiagonal component is found highly impurity-dependent. Considering the suitable Born–Mayer–Huggins

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7

Fuß, Werner, Evan G. Robertson, Chris Medcraft, and Dominique R. T. Appadoo. "Vibrational Anharmonicities and Reactivity of Tetrafluoroethylene." Journal of Physical Chemistry A 118, no. 29 (2014): 5391–99. http://dx.doi.org/10.1021/jp500811w.

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8

Massa, Néstor E., and Vólia Lemos. "Intrinsic anharmonicities in theBX42−orthorhombic sublattice." Physical Review B 33, no. 5 (1986): 3379–83. http://dx.doi.org/10.1103/physrevb.33.3379.

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9

Piepenbring, R., та M. K. Jammari. "Anharmonicities of γ-vibrations in 168Er". Nuclear Physics A 481, № 1 (1988): 81–93. http://dx.doi.org/10.1016/0375-9474(88)90474-5.

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10

Anda, André, Darius Abramavičius, and Thorsten Hansen. "Two-dimensional electronic spectroscopy of anharmonic molecular potentials." Physical Chemistry Chemical Physics 20, no. 3 (2018): 1642–52. http://dx.doi.org/10.1039/c7cp06583c.

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Two-dimensional electronic spectroscopy (2DES) is a powerful tool in the study of coupled electron–phonon dynamics, yet very little is known about how nonlinearities in the electron–phonon coupling, arising from anharmonicities in the nuclear potentials, affect the spectra.

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11

Xiang, Bo, Raphael F. Ribeiro, Adam D. Dunkelberger, et al. "Two-dimensional infrared spectroscopy of vibrational polaritons." Proceedings of the National Academy of Sciences 115, no. 19 (2018): 4845–50. http://dx.doi.org/10.1073/pnas.1722063115.

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We report experimental 2D infrared (2D IR) spectra of coherent light–matter excitations––molecular vibrational polaritons. The application of advanced 2D IR spectroscopy to vibrational polaritons challenges and advances our understanding in both fields. First, the 2D IR spectra of polaritons differ drastically from free uncoupled excitations and a new interpretation is needed. Second, 2D IR uniquely resolves excitation of hybrid light–matter polaritons and unexpected dark states in a state-selective manner, revealing otherwise hidden interactions between them. Moreover, 2D IR signals highlight

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12

Guo, Xiao, Qiwei Tian, Yongsong Wang, et al. "Phonon anharmonicities in 7-armchair graphene nanoribbons." Carbon 190 (April 2022): 312–18. http://dx.doi.org/10.1016/j.carbon.2022.01.029.

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13

Znojil, M. "Singular anharmonicities and the analytic continued fractions." Journal of Mathematical Physics 30, no. 1 (1989): 23–27. http://dx.doi.org/10.1063/1.528614.

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14

Jammari, M. K., та R. Piepenbring. "Anharmonicities of γ-vibrations in deformed nuclei". Nuclear Physics A 487, № 1 (1988): 77–91. http://dx.doi.org/10.1016/0375-9474(88)90130-3.

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15

Shirai, Koun, та Hiroshi Katayama-Yoshida. "Anharmonicities in optical spectra of α-rhombohedral boron". Physica B: Condensed Matter 263-264 (березень 1999): 791–94. http://dx.doi.org/10.1016/s0921-4526(98)01288-5.

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16

Znojil, Miloslav. "Pairs of anharmonicities and the double delta expansions." Physics Letters A 164, no. 2 (1992): 145–48. http://dx.doi.org/10.1016/0375-9601(92)90693-g.

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17

Calvo, F., and P. Parneix. "Amplification of Anharmonicities in Multiphoton Vibrational Action Spectra." ChemPhysChem 13, no. 1 (2011): 212–20. http://dx.doi.org/10.1002/cphc.201100690.

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18

Hassanzedeh, Parviz, and Karl K. Irikura. "Inexpensive vibrational anharmonicities from estimated derivatives: Diatomic molecules." Journal of Computational Chemistry 19, no. 11 (1998): 1315–24. http://dx.doi.org/10.1002/(sici)1096-987x(199808)19:11<1315::aid-jcc11>3.0.co;2-k.

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19

PAINULI, C. P., B. P. BAHUGUNA, and B. D. INDU. "MICROWAVE ATTENUATION IN ISOTOPICALLY DISORDERED ANHARMONIC CRYSTALS." International Journal of Modern Physics B 05, no. 12 (1991): 2093–107. http://dx.doi.org/10.1142/s021797929100081x.

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The impurity-anharmonicity interactions, along with anharmonicities, mass and force constant changes have been taken into account to investigate the expressions for microwave attenuation in anharmonic crystals. A remarkable change in the phonon frequency shifts and widths has been reported due to the defect anharmonicity interactions. The usual method of central and non-central force constant parameters has been ignored here and parameter free expressions have been reported.

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20

ATAULLAH ANSARI, M., VINOD ASHOKAN, and B. D. INDU. "PHONON HEAT CONDUCTIVITY OF InSb AND CdS." International Journal of Modern Physics B 25, no. 10 (2011): 1409–18. http://dx.doi.org/10.1142/s0217979211058778.

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The lattice thermal conductivity of InSb and CdS has been analyzed on the basis of the most acquiescent Callaway model in the temperature range 2–300.779 K and 2.296–283.565 K. To reinvigorate the effects of phonon anharmonicities, more rigorous expressions for the phonon–phonon interactions, resonance, impurity and interference scattering relaxation times have been introduced to theoretically justify the experimentally observed results. A fairly good agreement between theory and experiments has been presented.

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21

Abada, A., and D. Vautherin. "Anharmonicities of nuclear vibrations from periodic mean-field orbits." Physical Review C 45, no. 5 (1992): 2205–16. http://dx.doi.org/10.1103/physrevc.45.2205.

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22

Srivastava, Sunita, and Vishwamittar. "Energies of oscillators with mixed quartic and sextic anharmonicities." Molecular Physics 72, no. 6 (1991): 1285–97. http://dx.doi.org/10.1080/00268979100100911.

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23

Durand, J. C., та R. Piepenbring. "Anharmonicities of γ vibrations in odd-mass deformed nuclei". Physical Review C 54, № 1 (1996): 189–200. http://dx.doi.org/10.1103/physrevc.54.189.

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24

Golonzka, O., M. Khalil, N. Demirdöven, and A. Tokmakoff. "Vibrational Anharmonicities Revealed by Coherent Two-Dimensional Infrared Spectroscopy." Physical Review Letters 86, no. 10 (2001): 2154–57. http://dx.doi.org/10.1103/physrevlett.86.2154.

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25

Pathak, Anirban, and Swapan Mandal. "Classical and quantum oscillators of sextic and octic anharmonicities." Physics Letters A 298, no. 4 (2002): 259–70. http://dx.doi.org/10.1016/s0375-9601(02)00500-5.

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26

SCHOMMERS, W., P. VON BLANCKENHAGEN, and C. SYROS. "PHONONS AND NON-LINEAR DYNAMIC EXCITATIONS AT THE SURFACE OF SOLIDS." Modern Physics Letters B 06, no. 01 (1992): 23–32. http://dx.doi.org/10.1142/s0217984992000053.

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In this paper we report molecular dynamics (MD) results for the surface dynamics of realistic model systems (krypton, lead). It turned out that the layers at the surface perform an unusual center-of-mass motion perpendicular to the surface; this new excitation should be due to the anharmonicities at the surface. The generalized phonon density of states has been studied in the bulk as well as at the surface of the crystal. The MD results are discussed in connection with dynamical-matrix solutions.

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27

Mix, Hartmut, Joachim Sauer, Klaus-Peter Schröder, and Angela Merkel. "Vibrational properties of surface hydroxyls: Nonempirical model calculations including anharmonicities." Collection of Czechoslovak Chemical Communications 53, no. 10 (1988): 2191–202. http://dx.doi.org/10.1135/cccc19882191.

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Complete sets of harmonic, semidiagonal cubic as well as diagonal cubic and quartic force constants are reported for the internal coordinates of terminal, ≣SiOH, and bridging, ≣SiOH·Al≣, surface hydroxyls on silica and zeolites. They are obtained by numerical differentiation of analytically calculated gradients of the energy (SCF approximation, 6-31 G* basis set). A GF vibrational analysis is performed and after making a nonlinear transformation of the force constants into normal coordinates the anharmonicity constants are evaluated by perturbation theory. Comparison is made with the D2OH+ ion

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28

Mrudul, M. S., Siby Thomas, and K. M. Ajith. "Anharmonicities in the temperature-dependent bending rigidity of BC3 monolayer." Journal of Physics and Chemistry of Solids 146 (November 2020): 109574. http://dx.doi.org/10.1016/j.jpcs.2020.109574.

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29

Pathak, Anirban, and Swapan Mandal. "Classical and quantum oscillators of quartic anharmonicities: second-order solution." Physics Letters A 286, no. 4 (2001): 261–76. http://dx.doi.org/10.1016/s0375-9601(01)00401-7.

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30

Beaudet, Yvon, Laurent J. Lewis, and Mats Persson. "Surface anharmonicities and disordering on Ni(100) and Ni(110)." Physical Review B 50, no. 16 (1994): 12084–103. http://dx.doi.org/10.1103/physrevb.50.12084.

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31

Sokolov, A. I. "Fluctuations, higher order anharmonicities, and Landau expansion for barium titanate." Physics of the Solid State 51, no. 2 (2009): 351–55. http://dx.doi.org/10.1134/s1063783409020255.

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32

Fuß, Werner, Evan G. Robertson, Chris Medcraft, and Dominique R. T. Appadoo. "Correction and Addition to “Vibrational Anharmonicities and Reactivity of Tetrafluoroethylene”." Journal of Physical Chemistry A 118, no. 36 (2014): 8009–10. http://dx.doi.org/10.1021/jp507985p.

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33

Freund, J. "On the determination of interatomic potential anharmonicities from EXAFS measurements." Physics Letters A 157, no. 4-5 (1991): 256–60. http://dx.doi.org/10.1016/0375-9601(91)90062-d.

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34

Schriver, Louise, André Schriver, Stefan Peil, and Otto Schrems. "Hydrogen-bonded complexes of perfluoro-t-butanol with acetone and nitromethane in low temperature solutions and matrices." Canadian Journal of Chemistry 69, no. 10 (1991): 1520–27. http://dx.doi.org/10.1139/v91-225.

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Infrared spectra are reported for binary complexes between perfluoro-tert-butanol as proton donor and nitromethane and acetone as bases. The complexes have been investigated in low temperature solutions and in cryogenic matrices. The spectra have been evaluated in terms of frequency shifts (ΔVOH), half widths (FWHH) and anharmonicities (κ) caused by the hydrogen bonding of these complexes. The influence of the environment (solvents and solid matrices) as well as temperature on the spectra of the complexes has also been studied and is discussed in detail. Key words: hydrogen bonding, temperatur

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35

Савотченко, С. Е. "Локализация и трансформация нелинейных возбуждений вблизи границы раздела сред с различными знаками нелинейности". Журнал технической физики 89, № 2 (2019): 163. http://dx.doi.org/10.21883/jtf.2019.02.47063.2355.

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AbstractContact states at the interface of nonlinear media with anharmonicities of different signs are considered. A model that represents a boundary-value problem for the nonlinear Schrödinger equation is proposed. Several types of stationary states that depend on energy and describe local states in the vicinity of the interface, localization of nonlinear waves passing through the interface, and transformation of such waves are obtained for the system under study. Dispersion relations that make it possible to determine the energies of such states are derived. Explicit expressions for the ener

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36

INDU, B. D. "ENHANCED PHONON DENSITY OF STATES IN IMPURE ANHARMONIC CRYSTALS." Modern Physics Letters B 06, no. 26 (1992): 1665–72. http://dx.doi.org/10.1142/s0217984992001368.

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The expression for the density of states of an isotopically disordered anharmonic crystal is investigated with the help of double-time thermodynamic Green’s functions. The cubic and quartic anharmonicities are taken into account besides the force constant changes and mass differences caused by the substitutional isotopic impurities. It is found that the density of states can be separated into defect, anharmonic and interference terms. The density of states is considerably enhanced due to the defects and impurities present in a real crystal and shows strong temperature and impurity concentratio

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37

Paar, V., and N. Pavin. "Regularity–Partial Chaos–Regularity Transition and Overlapped KAM Scenarios in a Conservative System of Two Linearly Coupled Double-Well Oscillators." Modern Physics Letters B 17, no. 17 (2003): 941–48. http://dx.doi.org/10.1142/s0217984903006001.

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For linearly coupled double-well oscillators the regularity–partial chaos–regularity transition is found. First, an incomplete KAM scenario develops with increasing energy, from integrable pattern comprising in-phase and out-of-phase small elliptic orbits towards a partial chaos, with a deformed regular island immersed in a chaotic sea. At a critical energy a new deformed island appears as a mirror image. Above the critical energy the inverse KAM scenario leads to gradual destruction of partial chaos and to the appearance of large elliptic orbits which correspond to the large-amplitude limit g

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38

Lee, Myung Won, Massimo Mella, and Andrew M. Rappe. "Electronic quantum Monte Carlo calculations of atomic forces, vibrations, and anharmonicities." Journal of Chemical Physics 122, no. 24 (2005): 244103. http://dx.doi.org/10.1063/1.1924690.

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39

Muñoz-Caro, Camelia, and Alfonso Niño. "Effect of Anharmonicities on the Thermodynamic Properties of the Water Dimer†." Journal of Physical Chemistry A 101, no. 22 (1997): 4128–35. http://dx.doi.org/10.1021/jp9701348.

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40

Hunt, K. L. C. "Vibrational force constants and anharmonicities: Relation to polarizability and hyperpolarizability densities." Journal of Chemical Physics 103, no. 9 (1995): 3552–60. http://dx.doi.org/10.1063/1.470239.

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41

Freeman, G. R., N. H. March, and L. von Szentpály. "Universal relation between spectroscopic constants: a chaotic/fractal regime in anharmonicities." Journal of Molecular Structure: THEOCHEM 394, no. 1 (1997): 11–13. http://dx.doi.org/10.1016/s0166-1280(96)04879-8.

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42

Alheit, R., C. Hennig, R. Morgenstern, F. Vedel, and G. Werth. "Observation of instabilities in a Paul trap with higher-order anharmonicities." Applied Physics B Lasers and Optics 61, no. 3 (1995): 277–83. http://dx.doi.org/10.1007/bf01082047.

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43

Gu, Yingying, and Dmitri Babikov. "On the role of vibrational anharmonicities in a two-qubit system." Journal of Chemical Physics 131, no. 3 (2009): 034306. http://dx.doi.org/10.1063/1.3152487.

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44

Costard, Rene, Tobias Tyborski, and Benjamin P. Fingerhut. "Anharmonicities and coherent vibrational dynamics of phosphate ions in bulk H2O." Physical Chemistry Chemical Physics 17, no. 44 (2015): 29906–17. http://dx.doi.org/10.1039/c5cp04502a.

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45

Volpe, C., F. Catara, Ph Chomaz, M. V. Andrés, and E. G. Lanza. "Anharmonicities and non-linearities in the excitation of double giant resonances." Nuclear Physics A 589, no. 3 (1995): 521–34. http://dx.doi.org/10.1016/0375-9474(95)00195-7.

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46

Bansal, Meena, Sunita Srivastava, Mamta, and Vishwamittar. "Energy eigenvalues for double-well oscillators with mixed cubic—quartic anharmonicities." Chemical Physics Letters 195, no. 5-6 (1992): 505–8. http://dx.doi.org/10.1016/0009-2614(92)85552-l.

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47

De Almeida, Wagner B., and Alan Hinchliffe. "Mechanical and electrical anharmonicities in the hydrogen cyanide hydrogen-bonded clusters." Journal of Molecular Structure: THEOCHEM 204 (January 1990): 153–69. http://dx.doi.org/10.1016/0166-1280(90)85070-4.

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48

Soulayman, S. Sh. "Theoretical Melting Curves of Alkali Halides." Zeitschrift für Naturforschung A 47, no. 6 (1992): 753–60. http://dx.doi.org/10.1515/zna-1992-0606.

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AbstractAn analysis of the melting curves of alkali halides is given. The study is based on the Improved Unsymmetrized Self-Consistent Field Method (IUSCFM) for strongly anharmonic crystals with complex lattice and the energy, entropy and Ross’s criterions in calculating the melting curves of alkali halides. The anharmonicities up to sixth order have been taken into consideration. The energy criterion was proven to be the most correct one along the melting curves of the high pressure modification (CsCl structure) while the entropy and Ross's criterions lead to a little better agreement with ex

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49

CHEN, L. Y., and N. J. M. HORING. "STUDY OF LENNARD-JONES CLUSTERS: EFFECTS OF ANHARMONICITIES FAR FROM SADDLE POINTS." International Journal of High Speed Electronics and Systems 18, no. 01 (2008): 119–26. http://dx.doi.org/10.1142/s0129156408005199.

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We study the transition pathways of a Lennard-Jones cluster of seven particles in three dimensions. Low lying saddle points of the LJ cluster, which can be reached directly from a minimum without passing through another minimum, are identified without any presumption of their characteristics, nor of the product states they lead to. The probabilities are computed for paths going from a given minimum to the surrounding saddle points. These probabilities are directly related to prefactors in the rate formula. This determination of the rate prefactors includes all anharmonicities, near or far from

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50

Ashokan, Vinod, and B. D. Indu. "Anharmonic phonon–electron effects on phonon density of states in La2−xSrxCuO4." Modern Physics Letters B 29, no. 29 (2015): 1550177. http://dx.doi.org/10.1142/s0217984915501778.

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In the present work, the phonon density of states (PDOS) for [Formula: see text] crystal is investigated by using the double time thermodynamic Green’s function method via a non-perturbative approach. A newly formulated Hamiltonian is considered for the lattice dynamics of phonon, which includes the effects of electron–phonon interactions, lattice anharmonicities and the interacting isotopic impurities. The automated emergence of pairons and [Formula: see text] wave pairing mechanism appears as a salient features of the theory. The PDOS is found to be dependent on temperature, impurity concent

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