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Journal articles on the topic 'Gaussian-Type atomic orbitals'

Author: Grafiati

Published: 14 September 2024

Last updated: 31 July 2025

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1

Gomes, Andr� Severo Pereira, and Rog�rio Custodio. "Exact Gaussian expansions of Slater-type atomic orbitals." Journal of Computational Chemistry 23, no. 10 (2002): 1007–12. http://dx.doi.org/10.1002/jcc.10090.

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2

Desmarais, N., G. Dancausse, and S. Fliszár. "A simple quality test for self-consistent-field atomic orbitals." Canadian Journal of Chemistry 71, no. 2 (1993): 175–79. http://dx.doi.org/10.1139/v93-025.

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A quality test is proposed for SCF atomic orbitals, [Formula: see text] approximated as finite linear combinations of suitable basis functions [Formula: see text] The key is in a function, readily derived from the Hartree–Fock equation [Formula: see text] which is identically zero for true Hartree–Fock spin orbitals and not so for approximate orbitals. In this way, our test measures how closely approximate orbital descriptions approach the true Hartree–Fock limit and thus provides a quality ordering of orbital bases with respect to one another and with respect to that limit, in a scale uniquel

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3

Mohammed, Tawfik Mahmood. "Mathematical modeling of the electronic structure of Titanium dioxide \((TiO_2 )_6\) nanoparticles." University of Aden Journal of Natural and Applied Sciences 24, no. 2 (2022): 519–26. http://dx.doi.org/10.47372/uajnas.2020.n2.a19.

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The calculation of the number of atoms of the given dimensional nanoparticle, composed of different type atoms has been researched in this work. The calculations have been carried out for nanoparticles of titanium dioxide. Theoretical visual models have been configured, and quantum – mechanical calculations have been carried out for \((TiO_2 )_6\) nanoparticle. The calculations for titanium dioxide nanoparticle have been carried out on the basis of Gaussian atomic orbitals. Besides, Gaussian functions have been used as atomic orbitals. The numerical values of unknown coefficients of the linear

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4

Mitroy, J. "A Hartree - Fock Program for Atomic Structure Calculations." Australian Journal of Physics 52, no. 6 (1999): 973. http://dx.doi.org/10.1071/ph99042.

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The Hartree–Fock equations for a general open shell atom are described. The matrix equations that result when the single particle orbitals are written in terms of a linear combination of analytic basis functions are derived. Attention is paid to the complexities that occur when open shells are present. The specifics of a working FORTRAN program which is available for public use are described. The program has the flexibility to handle either Slater-type orbitals or Gaussian-type orbitals.

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5

Kuang, Jiyun, and C. D. Lin. "Molecular integrals over spherical Gaussian-type orbitals: I." Journal of Physics B: Atomic, Molecular and Optical Physics 30, no. 11 (1997): 2529–48. http://dx.doi.org/10.1088/0953-4075/30/11/007.

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6

J.E., Pérez, Cesco J.C., Alturria Lanzardo C.J., et al. "Considering a mixed atomic basis set composed of only 1s STO and 1s GTO in molecular calculations." Chemistry Research Journal 4, no. 1 (2019): 60–66. https://doi.org/10.5281/zenodo.13745087.

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An atomic basis set composed of only 1s orbitals is introduced, for molecular calculations in the Hartree-Fock-LCAO approximation. The 1s Slater Type Orbitals are located at the nuclei and the 1s Gaussian Type Orbitals can be used both in fixed locations and as Floating Orbitals. Surprisingly, despite the simplicity of the orbitals, this basis set provides an accurate description of molecular systems containing atoms with two shells such as oxygen and carbon, used as case studies in this work. From a numerical perspective, the basis set is first optimized for the free atoms and then they

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7

Dacosta, Herbert F. M., Milan Trsic, and Alfredo M. Simas. "Hydrogen-type orbitals in terms of Gaussian functions." International Journal of Quantum Chemistry 65, no. 2 (1997): 143–50. http://dx.doi.org/10.1002/(sici)1097-461x(1997)65:2<143::aid-qua5>3.0.co;2-w.

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8

Berlu, Lilian, and Philip Hoggan. "Useful Integrals for Ab-Initio Molecular Quantum Similarity Measurements Using Slater Type Atomic Orbitals." Journal of Theoretical and Computational Chemistry 02, no. 02 (2003): 147–61. http://dx.doi.org/10.1142/s0219633603000513.

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Molecular quantum similarity measurements are based on a quantitative comparison of the one-electron densities of two molecules superposed and aligned to optimize a well-defined similarity function. In most previous work the densities have been related using a Dirac delta leading to the overlap-like quantum similarity function. The densities for the two molecules compared have generally been approximated often with a simple LCAO of s-gaussian functions. In this work, we present a one center two range expansion method for the evaluation of the overlap integrals involved in the overlap-like quan

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9

Tanaka, Kiyoaki. "X-ray molecular orbital analysis. I. Quantum mechanical and crystallographic framework." Acta Crystallographica Section A Foundations and Advances 74, no. 4 (2018): 345–56. http://dx.doi.org/10.1107/s2053273318005478.

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Molecular orbitals were obtained by X-ray molecular orbital analysis (XMO). The initial molecular orbitals (MOs) of the refinement were calculated by the ab initio self-consistent field (SCF) MO method. Well tempered basis functions were selected since they do not produce cusps at the atomic positions on the residual density maps. X-ray structure factors calculated from the MOs were fitted to observed structure factors by the least-squares method, keeping the orthonormal relationship between MOs. However, the MO coefficients correlate severely with each other, since basis functions are compose

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10

Raynaud, Christophe, Laurent Maron, Jean-Pierre Daudey, and Franck Jolibois. "Reconsidering Car–Parrinello molecular dynamics using direct propagation of molecular orbitals developed upon Gaussian type atomic orbitals." Phys. Chem. Chem. Phys. 6, no. 17 (2004): 4226–32. http://dx.doi.org/10.1039/b402163k.

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11

Fernández Rico, J., R. López, I. Ema, and G. Ramírez. "Deformed atoms in molecules: analytical representation of atomic densities for Gaussian type orbitals." Journal of Molecular Structure: THEOCHEM 727, no. 1-3 (2005): 115–21. http://dx.doi.org/10.1016/j.theochem.2005.02.028.

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12

Njapba, S. Augustine, and Galadanci M. S. Garba. "Density functional theory study of the nuclear magnetic resonance properties and natural bond orbital analysis of germanium-phenyl nanocluster." Dutse Journal of Pure and Applied Sciences 10, no. 2c (2024): 162–75. http://dx.doi.org/10.4314/dujopas.v10i2c.16.

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In this study, the optimized molecular geometry and vibrational frequencies of novel germanium-phenyl nanostructure were calculated using the hybrid functional B3LYP/Lanl2dz as implemented in Gaussian 09 program. The obtained geometries from the calculations of density functional theory were used to carry out natural bond orbital analysis. The stabilization energy E2 that is related to the delocalization trend of electrons from donor to acceptor orbitals was also computed. The higher the stabilization energy E2, between a bonding orbital and an acceptor orbital the greater the interaction betw

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13

Pinchon, Didier, and Philip E. Hoggan. "Gaussian approximation of exponential type orbitals based on B functions." International Journal of Quantum Chemistry 109, no. 2 (2009): 135–44. http://dx.doi.org/10.1002/qua.21705.

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14

Wang, Jian, and Alexei A. Stuchebrukhov. "DFT calculation of electron tunneling currents: Real-space (grid) molecular orbitals vs. Gaussian-type molecular orbitals." International Journal of Quantum Chemistry 80, no. 4-5 (2000): 591–97. http://dx.doi.org/10.1002/1097-461x(2000)80:4/5<591::aid-qua8>3.0.co;2-j.

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15

Boettger, J. C., M. D. Jones, and R. C. Albers. "Structural properties of crystalline uranium from linear combination of Gaussian-type orbitals calculations." International Journal of Quantum Chemistry 75, no. 4-5 (1999): 911–15. http://dx.doi.org/10.1002/(sici)1097-461x(1999)75:4/5<911::aid-qua55>3.0.co;2-x.

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16

Kuang, Jiyun, and C. D. Lin. "Molecular integrals over spherical Gaussian-type orbitals: II. Modified with plane-wave phase factors." Journal of Physics B: Atomic, Molecular and Optical Physics 30, no. 11 (1997): 2549–67. http://dx.doi.org/10.1088/0953-4075/30/11/008.

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17

Platonenko, Alexander, Sergei Piskunov, Thomas C. K. Yang, et al. "Electronic Structure of Mg-, Si-, and Zn-Doped SnO2 Nanowires: Predictions from First Principles." Materials 17, no. 10 (2024): 2193. http://dx.doi.org/10.3390/ma17102193.

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We investigated the electronic structure of Mg-, Si-, and Zn-doped four-faceted [001]- and [110]-oriented SnO2 nanowires using first-principles calculations based on the linear combination of atomic orbitals (LCAO) method. This approach, employing atomic-centered Gaussian-type functions as a basis set, was combined with hybrid density functional theory (DFT). Our results show qualitative agreement in predicting the formation of stable point defects due to atom substitutions on the surface of the SnO2 nanowire. Doping induces substantial atomic relaxation in the nanowires, changes in the covale

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18

Boettger, Jonathan Carl. "Spin-polarized fully relativistic linear combinations of Gaussian-type orbitals calculations for fcc plutonium." International Journal of Quantum Chemistry 95, no. 4-5 (2003): 380–86. http://dx.doi.org/10.1002/qua.10588.

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19

Domnin, Anton V., Ilia E. Mikhailov, and Robert A. Evarestov. "DFT Study of WS2-Based Nanotubes Electronic Properties under Torsion Deformations." Nanomaterials 13, no. 19 (2023): 2699. http://dx.doi.org/10.3390/nano13192699.

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In this study, the influence of torsional deformations on the properties of chiral WS2-based nanotubes was investigated. All calculations presented in this study were performed using the density functional theory (DFT) and atomic gaussian type orbitals basis set. Nanotubes with chirality indices (8, 2), (12, 3), (24, 6) and (36, 9) corresponding to diameters of 10.68 Å, 14.90 Å, 28.26 Å and 41.90 Å, respectively, are examined. Our results reveal that for nanotubes with smaller diameters, the structure obtained through rolling from a slab is not optimal and undergoes spontaneous deformation. Fu

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20

Palmer, Michael H. "The ab initio Calculation of Nuclear Quadrupole Coupling Constants with Special Reference to 33S." Zeitschrift für Naturforschung A 47, no. 1-2 (1992): 203–16. http://dx.doi.org/10.1515/zna-1992-1-235.

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AbstractThe ab initio calculation of 33S nuclear quadrupole coupling constants (NQCC) for a range of S-containing compounds with S2, S4 and S6 bonding types is described. All of the calculations used a triple zeta valence + polarisation basis set (TZVP) of gaussian type orbitals; all of the molecules were studied at the TZVP equilibrium geometry. The electric field gradients (EFG) calculated were correlated with the experimental NQCC obtained by either microwave spectroscopy (MW), nuclear quadrupole resonance (NQR) or NMR relaxation methods; although the experimental data cover a wide diversit

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21

Ishida, Kazuhiro. "ACE algorithm for the rapid evaluation of the electron-repulsion integral over Gaussian-type orbitals." International Journal of Quantum Chemistry 59, no. 3 (1996): 209–18. http://dx.doi.org/10.1002/(sici)1097-461x(1996)59:3<209::aid-qua4>3.0.co;2-1.

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22

Safa, Sadaghiyanfam*, Kamberaj Hiqmet, and Isler Yalcin. "Interactive Graphical User Interface For Quantum Mechanics Simulations with Pyscf." Journal of Intelligent Systems with Applications 7, no. 2 (2024): 31–39. https://doi.org/10.5281/zenodo.14609675.

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This article presents a graphical user interface program developed in the Python programming language. This interface aims to make quantum mechanics simulations easier to perform using the PySCF package. paper presents a software written in Python programming language. The software offers many features to its users new opportunities on visualization, optimization, designing, and calculation for quantum mechanics and quantum gaming studies. Two explanatory examples are also implemented to show the efficiency of the interface. These examples are quantum gaming and virtual screening. Thanks to th

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23

Cesco, J. C., C. C. Denner, G. O. Giubergia, et al. "Implementation of atomic basis set composed of 1s Gaussian and 1s Slater-type orbitals to carry out quantum mechanics molecular calculations." Journal of Computational Chemistry 20, no. 6 (1999): 604–9. http://dx.doi.org/10.1002/(sici)1096-987x(19990430)20:6<604::aid-jcc6>3.0.co;2-o.

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24

Kalinin, N. V., and V. A. Saleev. "Ab initio modeling of Raman and infrared spectra of calcite." Computer Optics 42, no. 2 (2018): 263–66. http://dx.doi.org/10.18287/2412-6179-2018-42-2-263-266.

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Calcite is the most thermodynamically stable polymorphic phase of the CaCO3 crystal. It is widely used in modern optical instruments operating in the infrared and visible wavelengths of electromagnetic radiation. In particular, due to its anisotropic properties, calcite is used in polarization optics devices. Ab initio quantum mechanical modeling of the Raman and infrared spectra of calcite makes it possible to better understand the structure and nature of the chemical bonds of the compound, and find the optimal conditions for the effective use of unique properties of calcite in photonics tool

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25

Toader, Ana Maria, Maria Cristina Buta, and Fanica Cimpoesu. "On the calculation of lanthanide systems. The spectral parameters of praseodymium trivalent ion." Chemistry Journal of Moldova 18, no. 2 (2023): 78–86. http://dx.doi.org/10.19261/cjm.2023.1146.

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In this work, taking the Pr(III) ion as a suitable case study, the authors test the capacity of a series of Gaussian Type Orbitals (GTOs) basis sets to account for the atomic spectra of lanthanide ions. An extended relevance of this assessment can be found in modeling the luminescence of lanthanide-based materials. It was selected the Pr(III) case because it shows a rather rich collection of experimental data, emerging from the f2 and fd configurations. The energy barycenters of spectral multiplets can be equated analytically in terms of the so-called Slater-Condon parameters. By multi-configu

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26

Jursic, Branko S. "Computation of geometries and frequencies of singlet and triplet nitromethane with density functional theory using Gaussian-type orbitals." International Journal of Quantum Chemistry 64, no. 2 (1997): 263–69. http://dx.doi.org/10.1002/(sici)1097-461x(1997)64:2<263::aid-qua15>3.0.co;2-a.

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27

Rusevich, Leonid L., Mikhail G. Brik, Denis Gryaznov, et al. "First-Principles Linear Combination of Atomic Orbitals Calculations of K2SiF6 Crystal: Structural, Electronic, Elastic, Vibrational and Dielectric Properties." Materials 17, no. 19 (2024): 4865. http://dx.doi.org/10.3390/ma17194865.

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The results of first-principles calculations of the structural, electronic, elastic, vibrational, dielectric and optical properties, as well as the Raman and infrared (IR) spectra, of potassium hexafluorosilicate (K2SiF6; KSF) crystal are discussed. KSF doped with manganese atoms (KSF:Mn4+) is known for its ability to function as a phosphor in white LED applications due to the efficient red emission from Mn⁴⁺ activator ions. The simulations were performed using the CRYSTAL23 computer code within the linear combination of atomic orbitals (LCAO) approximation of the density functional theory (DF

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28

Ulian, Gianfranco, and Giovanni Valdrè. "Thermomechanical, electronic and thermodynamic properties of ZnS cubic polymorphs: an ab initio investigation on the zinc-blende–rock-salt phase transition." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 75, no. 6 (2019): 1042–59. http://dx.doi.org/10.1107/s2052520619012630.

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In the present work, an extensive and detailed theoretical investigation is reported on the thermomechanical, electronic and thermodynamic properties of zinc-blende (sphalerite, zb-ZnS) and rock-salt zinc sulfide (rs-ZnS) over a wide range of pressure, by means of ab initio Density Functional Theory, Gaussian type orbitals and the well known B3LYP functional. For the first time, vibrational frequencies, phonon dispersion relations, elasto-piezo-dielectric tensor, thermodynamic and thermomechanical properties of rs-ZnS were calculated with a consistent approach that allows a direct comparison w

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29

Hu, Anguang, and Brett I. Dunlap. "Three-center molecular integrals and derivatives using solid harmonic Gaussian orbital and Kohn–Sham potential basis sets." Canadian Journal of Chemistry 91, no. 9 (2013): 907–15. http://dx.doi.org/10.1139/cjc-2012-0485.

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Three-center integrals over Gaussian orbital and Kohn–Sham (KS) basis sets are reviewed. An orbital basis function carries angular momentum about its atomic center. That angular momentum is created by solid harmonic differentiation with respect to the center of an s-type basis function. That differentiation can be brought outside any purely s-type integral, even nonlocal pseudopotential integrals. Thus the angular factors associated with angular momentum and differentiation with respect to atom position can be pulled outside loops over orbital and KS Gaussian exponents.

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30

Kotlyar, V. V., A. A. Kovalev, and A. P. Porfirev. "Measurement of the orbital angular momentum of an astigmatic Hermite–Gaussian beam." Computer Optics 43, no. 3 (2019): 356–67. http://dx.doi.org/10.18287/2412-6179-2019-43-3-356-367.

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Here we study three different types of astigmatic Gaussian beams, whose complex amplitude in the Fresnel diffraction zone is described by the complex argument Hermite polynomial of the order (n, 0). The first type is a circularly symmetric Gaussian optical vortex with and a topological charge n after passing through a cylindrical lens. On propagation, the optical vortex "splits" into n first-order optical vortices. Its orbital angular momentum per photon is equal to n. The second type is an elliptical Gaussian optical vortex with a topological charge n after passing through a cylindrical lens.

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31

Pinheiro da Silva, Braian, Wagner T. Buono, Leonardo J. Pereira, Daniel S. Tasca, Kaled Dechoum, and Antonio Z. Khoury. "Spin to orbital angular momentum transfer in frequency up-conversion." Nanophotonics 11, no. 4 (2021): 771–78. http://dx.doi.org/10.1515/nanoph-2021-0493.

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Abstract We demonstrate the spin to orbital angular momentum transfer in frequency upconversion with structured light beams. A vector vortex is coupled to a circularly polarized Gaussian beam in noncollinear second harmonic generation under type-II phase match. The second harmonic beam inherits the Hermite–Gaussian components of the vector vortex; however, the relative phase between them is determined by the polarization state of the Gaussian beam. This effect creates an interesting crosstalk between spin and orbital degrees of freedom, allowing the angular momentum transfer between them. Our

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32

Jursic, Branko S. "Density functional calculations of difluorodiazete structures with Gaussian-orbital-type approach." International Journal of Quantum Chemistry 57, no. 2 (1996): 213–17. http://dx.doi.org/10.1002/(sici)1097-461x(1996)57:2<213::aid-qua7>3.0.co;2-0.

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33

Lasar, Christian, and Thorsten Klüner. "Explicitly correlated orbital optimized contracted pair correlation methods: Foundations and applications." Journal of Theoretical and Computational Chemistry 17, no. 04 (2018): 1850024. http://dx.doi.org/10.1142/s0219633618500244.

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Pair correlation methods are able to achieve highly accurate solutions for chemical problems. Unfortunately, their applicability is generally restricted to medium-sized molecules due to storage requirements and computational costs. These restrictions can be partly overcome by local correlation methods. These methods use physical and mathematical criteria to decide which interactions are of such a long range that they do not have to be computed and saved. In our new ansatz, we define an alternative way towards local correlation. The range of interactions is strictly bound to the decay of integr

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34

Saleev, Vladimir, and Alexandra Shipilova. "First-principles calculations of LiNbO3 optical properties: From far-infrared to ultraviolet." Modern Physics Letters B 32, no. 05 (2018): 1850063. http://dx.doi.org/10.1142/s021798491850063x.

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We perform first-principles calculations of optical properties for ferroelectric phase of LiNbO3 crystal using density functional theory (DFT) for wide range of wavelengths, from far-infrared (IR) to ultraviolet. We study frequency dependence of complex dielectric tensor and related quantities, such as refractive and reflection indices, absorption coefficients, etc. Our calculation incorporates advantages of numerical approaches based on atomic-orbital all-electron Gaussian-type basis sets, as it is realized in CRYSTAL14 program. We compared predictions obtained in general-gradient approach wi

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35

Coursault, Delphine, and Etienne Brasselet. "Nanostructured silica spin–orbit optics for modal vortex beam shaping." Nanophotonics 11, no. 4 (2021): 805–12. http://dx.doi.org/10.1515/nanoph-2021-0579.

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Abstract Modality is a generic concept of wave-optics at the basis of optical information and communications. One of the challenges of photonics technologies based on optical orbital angular momentum consists in the production of a modal content for both the azimuthal and radial degrees of freedom. This basically requires shaping the complex amplitude of an incident light beam, which is usually made up from adaptive spatial light modulators or bespoke devices. Here, we report on the experimental attempt of a recent theoretical proposal [Opt. Lett. 42, 1966 (2017)] toward the production of vari

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36

Ishimoto, Takayoshi, Masanori Tachikawa, and Umpei Nagashima. "Analytical optimization of exponent values in protonic and deuteronic Gaussian-type functions by elimination of translational and rotational motions from multi-component molecular orbital scheme." International Journal of Quantum Chemistry 108, no. 3 (2007): 472–81. http://dx.doi.org/10.1002/qua.21540.

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37

Jursic, Branko S., and Zoran Zdravkovski. "Theoretical investigation of the conrotatory ring opening of cyclobutene and 1, 2-dihydro-1, 2-diazacyclobutadienes with ab initio and density functional Gaussian-type-orbital approach." International Journal of Quantum Chemistry 56, no. 2 (1995): 115–23. http://dx.doi.org/10.1002/qua.560560206.

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38

Mathar, Richard J. "Erratum: Mutual conversion of three flavors of gaussian type orbitals." International Journal of Quantum Chemistry, 2009, NA. http://dx.doi.org/10.1002/qua.22353.

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39

Shaw, Robert A. "The completeness properties of Gaussian‐type orbitals in quantum chemistry." International Journal of Quantum Chemistry 120, no. 17 (2020). http://dx.doi.org/10.1002/qua.26264.

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40

Lehtola, Susi. "Importance profiles. Visualization of atomic basis set requirements." Electronic Structure, March 8, 2024. http://dx.doi.org/10.1088/2516-1075/ad31ca.

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Abstract Recent developments in fully numerical methods promise interesting opportunities for new, compact atomic orbital (AO) basis sets that maximize the overlap to fully numerical reference wave functions, following the pioneering work of Richardson and coworkers from the early 1960s. Motivated by this technique, we suggest a way to visualize the importance of AO basis functions employing fully numerical wave functions computed at the complete basis set (CBS) limit: the importance of a normalized AO basis function |α⟩ centered on some&#xD;nucleus can P be visualized by projecting |α⟩ on

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41

Gangal, Krish, İpek Gerz, Tanvi Goyal, Ajeeth Iyer, Vaibhav Vaiyakarnam, and Larry McMahan. "Modeling Hartree-Fock approximations of the Schrödinger Equation for multielectron atoms from Helium to Xenon using STO-nG basis sets." Journal of Emerging Investigators, 2023. http://dx.doi.org/10.59720/22-211.

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The energy of an atom is extremely useful in nuclear physics and reaction mechanism pathway determination but is challenging to compute. Thus, we aimed to synthesize regression models for Pople Gaussian expansions of Slater-type Orbitals (STO-nG) atomic energy vs. atomic number scatter plots to allow for easy approximation of atomic energies without using computational chemistry methods. Using the Hartree-Fock method, we calculated atomic energies for elements helium to xenon (He to Xe) using STO-nG electron orbital basis set models. After calculating atomic energies for each basis set, we plo

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42

Qin, Xinming, Honghui Shang, and Jinlong Yang. "Efficient implementation of analytical gradients for periodic hybrid functional calculations within fitted numerical atomic orbitals from NAO2GTO." Frontiers in Chemistry 11 (July 27, 2023). http://dx.doi.org/10.3389/fchem.2023.1232425.

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The NAO2GTO scheme provides an efficient way to evaluate the electron repulsion integrals (ERIs) over numerical atomic orbitals (NAOs) with auxiliary Gaussian-type orbitals (GTOs). However, the NAO2GTO fitting will significantly impact the accuracy and convergence of hybrid functional calculations. To address this issue, here we propose to use the fitted orbitals as a new numerical basis to properly handle the mismatch between NAOs and fitted GTOs. We present an efficient and linear-scaling implementation of analytical gradients of Hartree-Fock exchange (HFX) energy for periodic HSE06 calculat

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43

Kim, Inkoo, Daun Jeong, Won-Joon Son, et al. "Kohn–Sham time-dependent density functional theory with Tamm–Dancoff approximation on massively parallel GPUs." npj Computational Materials 9, no. 1 (2023). http://dx.doi.org/10.1038/s41524-023-01041-4.

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AbstractWe report a high-performance multi graphics processing unit (GPU) implementation of the Kohn–Sham time-dependent density functional theory (TDDFT) within the Tamm–Dancoff approximation. Our algorithm on massively parallel computing systems using multiple parallel models in tandem scales optimally with material size, considerably reducing the computational wall time. A benchmark TDDFT study was performed on a green fluorescent protein complex composed of 4353 atoms with 40,518 atomic orbitals represented by Gaussian-type functions, demonstrating the effect of distant protein residues on

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44

Esteve-Paredes, Juan José, and Juan José Palacios. "A comprehensive study of the velocity, momentum and position matrix elements for Bloch states: Application to a local orbital basis." SciPost Physics Core 6, no. 1 (2023). http://dx.doi.org/10.21468/scipostphyscore.6.1.002.

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We present a comprehensive study of the velocity operator, \hat{\boldsymbol{v}}=\frac{i}{\hbar} [\hat{H},\hat{\boldsymbol{r}}]\,𝐯̂=iℏ[Ĥ,𝐫̂], when used in crystalline solids calculations. The velocity operator is key to the evaluation of a number of physical properties and its computation, both from a practical and fundamental perspective, has been a long-standing debate for decades. Our work summarizes the different approaches found in the literature, but never connected before in a comprehensive manner. In particular we show how one can compute the velocity matrix elements following two diff

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45

Kang, Byungkyun, Joshua Vincent, Yongbin Lee, Liqin Ke, Peter A. Crozier, and Qiang Zhu. "Modeling surface spin polarization on ceria-supported Pt nanoparticles." Journal of Physics: Condensed Matter, March 30, 2022. http://dx.doi.org/10.1088/1361-648x/ac62a3.

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Abstract In this work, we employ density functional theory simulations to investigate possible spin polarization of CeO$_2$-(111) surface and its impact on the interactions between a ceria support and Pt nanoparticles. With a Gaussian type orbital basis, our simulations suggest that the CeO$_2$-(111) surface exhibits a robust surface spin polarization due to the internal charge transfer between atomic Ce and O layers. In turn, it can lower the surface oxygen vacancy formation energy and enhance the oxide reducibility. We show that the inclusion of spin polarization can significantly reduce the

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Mendoza-López, L. A., J. G. Acosta-Montes, J. A. Bernal-Orozco, et al. "Frequency Conversion of Optical Vortex Arrays Through Four-Wave Mixing in Hot Atomic Gases." Frontiers in Physics 10 (July 11, 2022). http://dx.doi.org/10.3389/fphy.2022.895023.

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Arrays of multiple vortices were transferred from infrared to the blue region of the optical spectrum. This demonstration was achieved by inducing four-wave mixing in an atomic gas with a Gaussian beam and a quasi-invariant propagation beam of the Mathieu type. The latter structure was analyzed in the Fourier space for the pump and the generated light. In both cases, the phase structure can be written with a compact mathematical expression by using the same parameters within experimental error bars. A Michelson–Morley interferometer was used to confirm that a phase singularity was present at e

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Slama, Marwa, Hela Habli, Soulef Jellali, and Mounir Ben El Hadj Rhouma. "Computational study of the electronic structure of the Sr^m+Kr (m=0, 1) van der Waals complexes." Physica Scripta, June 21, 2022. http://dx.doi.org/10.1088/1402-4896/ac7aea.

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Abstract A computational study of the electronic structure of the SrKr and Sr+Kr molecular systems is presented in this paper. The computational scheme is based on the Full Configuration Interaction (FCI) method and semi-empirical pseudo-potential approach of the atomic core Sr2+ with Gaussian-type-orbital (GTO) basis sets. We have calculated the potential energy surfaces (PESs), spectroscopic parameters, electric dipole moments, and the vibrational levels' spacing for the electronic states of the SrKr molecule and its Sr+Kr ion. The accuracy of the current spectroscopic results is discussed b

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Savvidi, Kamila, Ludwig Ahrens-Iwers, Lucio Colombi Ciacchi, Dirk Zahn, Martin H. Müser, and Robert Horst Meißner. "Efficient treatment of long-range electrostatics in charge equilibration approaches." Journal of Chemical Physics 162, no. 17 (2025). https://doi.org/10.1063/5.0255823.

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A charge equilibration method based on real-space Gaussians as charge densities is presented. The implementation is part of the Electrode package available in the Large-scale Atomic/Molecular Massively Parallel Simulator and benefits from its efficient particle-mesh Ewald approach. A simple strategy required to switch from the previously used Slater-type orbital (STO) shielding to Gaussians is provided by fitting the Coulomb energy of two Gaussian charge distributions to the repulsion between two STOs. Their widths were optimized for O, Si, and Ti species, obtaining results consistent with pre

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Li, Shanggeng, Fanghua Zhu, Yawen Zhou та ін. "First theoretical probe for alkynyl bridged thiophene modified coumarin nonlinear optical materials with D-π-A and A-π-D-π-A structures". Journal of Nonlinear Optical Physics & Materials 31, № 02 (2022). http://dx.doi.org/10.1142/s0218863522500084.

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First-principles exploration is very important to molecular design. In this study, geometric structure, intramolecular charge transfer (ICT), energy levels, polar moment, and ultraviolet–visible (UV–Vis) spectroscopy of eight novel and different alkynyl bridged thiophene modified coumarin nonlinear optical molecules with [Formula: see text]-[Formula: see text]-[Formula: see text] and [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] structures had been studied by density-functional theory (DFT) calculations within B3LYP hybrid functional using

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Ibrahim, Muhammad, Rahmat ullah, and Sajid Qamar. "Excitation of Surface Plasmon Polaritons via Composite Structured Light." Physica Scripta, May 15, 2025. https://doi.org/10.1088/1402-4896/add970.

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Abstract We propose a scheme for the excitation of surface plasmon polaritons (SPPs) at a metal-dielectric interface utilizing composite structured light. The proposed system is based on a three-layer structure, consisting of an upper transparent medium, a central metallic thin film, and a lower dielectric layer incorporating a four-level atomic system with an N-type configuration. We employ a weak probe field and two coupling fields, with the second coupling field being a composite vortex beam formed by the superposition of two Laguerre-Gaussian (LG) beams. We analyze the permittivity of the

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