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A B F Da Silva - One of the best experts on this subject based on the ideXlab platform.
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a universal gaussian basis set for atoms cerium through lawrencium generated with the generator coordinate hartree fock Method
Journal of Computational Chemistry, 1997Co-Authors: F E Jorge, E V R De Castro, A B F Da SilvaAbstract:The generator coordinate Hartree–Fock Method is applied to generate a universal Gaussian basis set for the heavy atoms from Ce (Z=58) through Lr (Z=103). The Hartree–Fock energies obtained with our universal Gaussian basis set are compared with the new numerical Hartree–Fock results of Koga et al., when available, and with geometrical Gaussian basis sets results available in the literature. The universal Gaussian basis set presented here is generated taking into account the shell constraint (the sharing of exponential functions between all s, p, d, and f atomic orbitals), and can be used as starting basis set in ab initio relativistic Hartree–Fock–Roothaan calculations. © 1997 John Wiley & Sons, Inc. J Comput Chem18: 1565–1569, 1997
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accurate universal gaussian basis set for hydrogen through lanthanum generated with the generator coordinate hartree fock Method
Chemical Physics, 1997Co-Authors: F E Jorge, E V R De Castro, A B F Da SilvaAbstract:Abstract The generator coordinate Hartree-Fock Method is applied to generate an accurate universal Gaussian basis set for the atoms H ( Z = 1) through La ( Z = 57). The Hartree-Fock energy results obtained with our universal Gaussian basis set are compared with numerical Hartree-Fock results and with Hartree-Fock energy results obtained by using optimized Gaussian basis sets. For the atoms B through Ca we have obtained, when compared to the corresponding numerical Hartree-Fock results, an energy value within the accuracy of 10 −5 –10 −4 E h , and for Sc through La this accuracy lies between 10 −4 and 10 −3 E h . The universal Gaussian basis set presented in this work is generated taking into account the sharing of exponential functions between all s, p and d atomic orbitals, i.e. the shell constraint.
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The generator coordinate Hartree-Fock Method for molecular systems. Formalism and first applications to H2, LiH and Li2
Chemical Physics, 1991Co-Authors: H.f.m. Da Costa, A B F Da Silva, J.r. Mohallem, Alfredo M. Simas, Milan TrsicAbstract:Abstract The generator coordinate Hartree-Fock Method is extended to molecular systems. The resulting equations are integrated numerically through discretization. The Method is then implemented with the use of the GAUSSIAN 86 program and applied to the H 2 , LiH and Li 2 diatomic species. The ground state Hartree-Fock energies (and dipole moment in the case of LiH) are calculated and compared with numerical Hartree-Fock values. The role of the molecular weight functions is discussed.
F E Jorge - One of the best experts on this subject based on the ideXlab platform.
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adapted gaussian basis sets for atoms from li through xe generated with the generator coordinate hartree fock Method
Anais Da Academia Brasileira De Ciencias, 2001Co-Authors: E V R De Castro, F E JorgeAbstract:The generator coordinate Hartree-Fock Method is used to generate adapted Gaussian basis sets for the atoms from Li (Z=3) through Xe (Z=54). In this Method the Griffin-Hill-Wheeler-Hartree-Fock equations are integrated through the integral discretization technique. The wave functions generated in this work are compared with the widely used Roothaan-Hartree-Fock wave functions of Clementi and Roetti (1974), and with other basis sets reported in the literature. For all atoms studied, the errors in our total energy values relatively to the numerical Hartree-Fock limits are always less than 7.426 mhartree.
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an improved generator coordinate hartree fock Method applied to the choice of contracted gaussian basis sets for first row diatomic molecules
International Journal of Quantum Chemistry, 2000Co-Authors: J C Pinheiro, F E Jorge, E V R De CastroAbstract:Accurate Gaussian basis sets (18s for Li and Be and 20s11p for the atoms from B to Ne) for the first-row atoms, generated with an improved generator coordinate Hartree–Fock Method, were contracted and enriched with polarization functions. These basis sets were tested for B2, C2, BeO, CN−, LiF, N2, CO, BF, NO+, O2, and F2. At the Hartree–Fock (HP), second-order Moller–Plesset (MP2), fourth-order Moller–Plesset (MP4), and density functional theory (DFT) levels, the dipole moments, bond lengths, and harmonic vibrational frequencies were studied, and at the MP2, MP4, and DFT levels, the dissociation energies were evaluated and compared with the corresponding experimental values and with values obtained using other contracted Gaussian basis sets and numerical HF calculations. For all diatomic molecules studied, the differences between our total energies, obtained with the largest contracted basis set [6s5p3d1f], and those calculated with the numerical HF Methods were always less than 3.2 mhartree. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 78: 15–23, 2000
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An improved generator coordinate Hartree–Fock Method applied to the choice of contracted Gaussian basis sets for first‐row diatomic molecules
International Journal of Quantum Chemistry, 2000Co-Authors: J C Pinheiro, F E Jorge, E V R De CastroAbstract:Accurate Gaussian basis sets (18s for Li and Be and 20s11p for the atoms from B to Ne) for the first-row atoms, generated with an improved generator coordinate Hartree–Fock Method, were contracted and enriched with polarization functions. These basis sets were tested for B2, C2, BeO, CN−, LiF, N2, CO, BF, NO+, O2, and F2. At the Hartree–Fock (HP), second-order Moller–Plesset (MP2), fourth-order Moller–Plesset (MP4), and density functional theory (DFT) levels, the dipole moments, bond lengths, and harmonic vibrational frequencies were studied, and at the MP2, MP4, and DFT levels, the dissociation energies were evaluated and compared with the corresponding experimental values and with values obtained using other contracted Gaussian basis sets and numerical HF calculations. For all diatomic molecules studied, the differences between our total energies, obtained with the largest contracted basis set [6s5p3d1f], and those calculated with the numerical HF Methods were always less than 3.2 mhartree. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 78: 15–23, 2000
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accurate gaussian basis sets for second row atoms and ions generated with the improved generator coordinate hartree fock Method
Principles and Practice of Constraint Programming, 1999Co-Authors: E V R De Castro, F E Jorge, J C PinheiroAbstract:Abstract The improved generator coordinate Hartree–Fock (IGCHF) Method is used to generate accurate Gaussian basis sets for the second-row neutral atoms, singly charged cations from Na + through Ar + , and stable singly charged anions from Na − through Cl − . For all second-row atoms and ions studied, the ground-state energies obtained with the triply-optimized Gaussian basis sets (generated with the IGCHF Method) are always better than those obtained with the original generator coordinate Hartree–Fock Method, and do not differ from the corresponding numerical Hartree–Fock results by more than 0.8 millihartree.
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a universal gaussian basis set for atoms cerium through lawrencium generated with the generator coordinate hartree fock Method
Journal of Computational Chemistry, 1997Co-Authors: F E Jorge, E V R De Castro, A B F Da SilvaAbstract:The generator coordinate Hartree–Fock Method is applied to generate a universal Gaussian basis set for the heavy atoms from Ce (Z=58) through Lr (Z=103). The Hartree–Fock energies obtained with our universal Gaussian basis set are compared with the new numerical Hartree–Fock results of Koga et al., when available, and with geometrical Gaussian basis sets results available in the literature. The universal Gaussian basis set presented here is generated taking into account the shell constraint (the sharing of exponential functions between all s, p, d, and f atomic orbitals), and can be used as starting basis set in ab initio relativistic Hartree–Fock–Roothaan calculations. © 1997 John Wiley & Sons, Inc. J Comput Chem18: 1565–1569, 1997
E V R De Castro - One of the best experts on this subject based on the ideXlab platform.
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adapted gaussian basis sets for atoms from li through xe generated with the generator coordinate hartree fock Method
Anais Da Academia Brasileira De Ciencias, 2001Co-Authors: E V R De Castro, F E JorgeAbstract:The generator coordinate Hartree-Fock Method is used to generate adapted Gaussian basis sets for the atoms from Li (Z=3) through Xe (Z=54). In this Method the Griffin-Hill-Wheeler-Hartree-Fock equations are integrated through the integral discretization technique. The wave functions generated in this work are compared with the widely used Roothaan-Hartree-Fock wave functions of Clementi and Roetti (1974), and with other basis sets reported in the literature. For all atoms studied, the errors in our total energy values relatively to the numerical Hartree-Fock limits are always less than 7.426 mhartree.
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accurate gaussian basis sets for second row atoms and ions generated with the improved generator coordinate hartree fock Method
Principles and Practice of Constraint Programming, 1999Co-Authors: E V R De Castro, F E Jorge, J C PinheiroAbstract:Abstract The improved generator coordinate Hartree–Fock (IGCHF) Method is used to generate accurate Gaussian basis sets for the second-row neutral atoms, singly charged cations from Na + through Ar + , and stable singly charged anions from Na − through Cl − . For all second-row atoms and ions studied, the ground-state energies obtained with the triply-optimized Gaussian basis sets (generated with the IGCHF Method) are always better than those obtained with the original generator coordinate Hartree–Fock Method, and do not differ from the corresponding numerical Hartree–Fock results by more than 0.8 millihartree.
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a universal gaussian basis set for atoms cerium through lawrencium generated with the generator coordinate hartree fock Method
Journal of Computational Chemistry, 1997Co-Authors: F E Jorge, E V R De Castro, A B F Da SilvaAbstract:The generator coordinate Hartree–Fock Method is applied to generate a universal Gaussian basis set for the heavy atoms from Ce (Z=58) through Lr (Z=103). The Hartree–Fock energies obtained with our universal Gaussian basis set are compared with the new numerical Hartree–Fock results of Koga et al., when available, and with geometrical Gaussian basis sets results available in the literature. The universal Gaussian basis set presented here is generated taking into account the shell constraint (the sharing of exponential functions between all s, p, d, and f atomic orbitals), and can be used as starting basis set in ab initio relativistic Hartree–Fock–Roothaan calculations. © 1997 John Wiley & Sons, Inc. J Comput Chem18: 1565–1569, 1997
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accurate universal gaussian basis set for hydrogen through lanthanum generated with the generator coordinate hartree fock Method
Chemical Physics, 1997Co-Authors: F E Jorge, E V R De Castro, A B F Da SilvaAbstract:Abstract The generator coordinate Hartree-Fock Method is applied to generate an accurate universal Gaussian basis set for the atoms H ( Z = 1) through La ( Z = 57). The Hartree-Fock energy results obtained with our universal Gaussian basis set are compared with numerical Hartree-Fock results and with Hartree-Fock energy results obtained by using optimized Gaussian basis sets. For the atoms B through Ca we have obtained, when compared to the corresponding numerical Hartree-Fock results, an energy value within the accuracy of 10 −5 –10 −4 E h , and for Sc through La this accuracy lies between 10 −4 and 10 −3 E h . The universal Gaussian basis set presented in this work is generated taking into account the sharing of exponential functions between all s, p and d atomic orbitals, i.e. the shell constraint.
B. A. Brown - One of the best experts on this subject based on the ideXlab platform.
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Nuclear charge densities with the Skyrme Hartree-Fock Method
Physical Review C, 2003Co-Authors: W. A. Richter, B. A. BrownAbstract:Charge-density distributions and the associated nuclear radii are calculated with the Hartree-Fock Method for comparison with available data from electron scattering. Two forms of Skyrme interactions are used for the calculations. As a further refinement the single-particle occupancies are constrained to values obtained from shell-model calculations. A significant improvement in the agreement is obtained if shell-model occupancies are used.
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Displacement energies with the Skyrme Hartree–Fock Method
Physics Letters B, 2000Co-Authors: B. A. Brown, W. A. Richter, Robert S. LindsayAbstract:Abstract The binding energy differences of mirror nuclei are calculated with the Skyrme Hartree–Fock Method and compared to experiment. The Nolen–Schiffer anomaly can be accounted for either by dropping the Coulomb exchange term or by introducing a charge-symmetry breaking interaction. The displacement energy systematics can be quantitatively reproduced with either of these modifications. The results are important for an accurate description of the proton and neutron drip lines. The possible origins of these modifications in terms of nuclear correlations and nucleon-nucleon charge-symmetry breaking interactions are discussed.
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Displacement energies with the Skyrme Hartree–Fock Method
Physics Letters B, 2000Co-Authors: B. A. Brown, W. A. Richter, R LindsayAbstract:The binding energy differences of mirror nuclei are calculated with the Skyrme Hartree-Fock Method and compared to experiment. The Nolen-Schiffer anomaly can be accounted for either by dropping the Coulomb exchange term or by introducing a charge-symmetry breaking interaction. The displacement energy systematics can be quantitatively reproduced with either of these modifications. The results are important for an accurate description of the proton and neutron drip lines. The possible origins of these modifications in terms of nuclear correlations and nucleon-nucleon charge-symmetry breaking interactions are discussed. (C) 2000 Elsevier Science B.V.Articl
Kaoru Yamanouchi - One of the best experts on this subject based on the ideXlab platform.
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Decomposition of the configuration-interaction coefficients in the multiconfiguration time-dependent Hartree-Fock Method
The Journal of chemical physics, 2016Co-Authors: Erik Lötstedt, Tsuyoshi Kato, Kaoru YamanouchiAbstract:An approximate implementation of the multiconfiguration time-dependent Hartree-Fock Method is proposed, in which the matrix of configuration-interaction coefficients is decomposed into a product of matrices of smaller dimension. The applicability of this Method in which all the configurations are kept in the expansion of the wave function, while the configuration-interaction coefficients are approximately calculated, is discussed by showing the results on three model systems: a one-dimensional model of a beryllium atom, a one-dimensional model of a carbon atom, and a one-dimensional model of a chain of four hydrogen atoms. The time-dependent electronic dynamics induced by a few-cycle, long-wavelength laser pulse is found to be well described at a lower computational cost compared to the standard multiconfiguration time-dependent Hartree-Fock treatment. Drawbacks of the Method are also discussed.
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natural orbitals and potential curves within the framework of extended multi configuration time dependent hartree fock Method
19th International Conference on Ultrafast Phenomena (2014) paper 07.Mon.P1.16, 2014Co-Authors: Yoshihiro Ide, Tsuyoshi Kato, Kaoru YamanouchiAbstract:The extended multi-configuration time-dependent Hartree-Fock Method is proposed to calculate time-dependent wave functions. By constructing the ground-state wave function of one-dimensional H2 by imaginary time-propagation, the natural orbitals and the potential energy curves were derived.
