Gaussian basis sets for low-lying excited states of neutral atoms with 2 ≤ Z ≤ 36

2004 ◽  
Vol 82 (8) ◽  
pp. 1237-1243
Author(s):  
M T Barreto ◽  
A Canal Neto ◽  
F E Jorge
Keyword(s):  
Excited States ◽  
Standard Procedure ◽  
Basis Sets ◽  
Neutral Atoms ◽  
Gaussian Basis Sets ◽  
Excitation Energies ◽  
Hartree Fock ◽  
Generator Coordinate ◽  
Polarization Functions ◽  
Experimental Values

The improved generator coordinate Hartree–Fock method is used to generate Gaussian basis sets for low-lying excited states of neutral atoms from He (Z = 2) to Kr (Z = 36). Then, excitation energies and orbital energies of the outermost orbitals of each symmetry are calculated and compared with the corresponding values obtained with numerical Hartree–Fock calculations. Besides this, the basis sets for Be (3P) and F (2P) are contracted by a standard procedure and, then, enriched with polarization functions. From these basis sets, total energies, dissociation energy, and bond length for BeF are calculated and compared with results obtained with other basis sets and with experimental values. The sets for He–Kr are useful in constructing basis sets for molecular calculations. Key words: improved generator coordinate Hartree–Fock method, Gaussian basis sets, low-lying excited states, neutral atoms.

Gaussian basis sets for the atoms from K through Xe

2001 ◽  
Vol 79 (2) ◽  
pp. 121-123 ◽  
Author(s):  
R Centoducatte ◽  
E VR de Castro ◽  
F E Jorge
Keyword(s):  
Key Words ◽  
Ground State ◽  
Basis Sets ◽  
Gaussian Basis Sets ◽  
Hartree Fock ◽  
Generator Coordinate ◽  
Discretization Technique ◽  
Total Energies

An improved generator coordinate Hartree-Fock (IGCHF) method is used to generate Gaussian basis sets for the atoms from K (Z = 19) through Xe (Z = 54). The Griffin-Hill-Wheeler-HF equations are integrated using the integral discretization technique. The ground state HF total energies obtained by us are compared with those calculated with the original GCHF method and with other approaches reported in the literature. The largest difference between our energy values and the corresponding ones computed with a numerical HF method is equal to 6.003 mhartree for Kr (Z = 36).Key words: improved generator coordinate Hartree-Fock method, Gaussian basis sets, total energies.

Generation, contraction, and polarisation of Gaussian basis sets for atomic and molecular calculations using the generator coordinate method with polynomial discretisation: atoms from Na through Cl

2021 ◽  
Author(s):  
Amanda Ribeiro Guimaraes ◽  
Rugles César Barbosa ◽  
Ana Cristina Tello Mora ◽  
Aldineia Pereira da Silva ◽  
Júlia Maria Aragon Alves ◽  
...  
Keyword(s):  
Basis Sets ◽  
Gaussian Basis Sets ◽  
Generator Coordinate Method ◽  
Coordinate Method ◽  
Hartree Fock ◽  
Generator Coordinate ◽  
Molecular Calculations

The polynomial Generator Coordinate Hartree-Fock Gaussian basis sets, pGCHF, for the atoms Na, Mg, Al, Si, P, S, and Cl were generated using the generator coordinate method based on polynomial...

scholarly journals Quantum Mechanical Study of YTiO3 to the Investigation of Piezoelectricity

2011 ◽  
Vol 2011 ◽  
pp. 1-5
Author(s):  
Raimundo Dirceu de Paula Ferreira ◽  
Marcos Antonio Barros dos Santos ◽  
Maycon da Silva Lobato ◽  
Jardel Pinto Barbosa ◽  
Marcio de Souza Farias ◽  
...  
Keyword(s):  
Total Energy ◽  
Piezoelectric Properties ◽  
Piezoelectric Effect ◽  
Basis Set ◽  
Basis Sets ◽  
Gaussian Basis Sets ◽  
Hartree Fock ◽  
Generator Coordinate ◽  
Mechanical Study ◽  
Quantum Mechanical Study

In previous articles we reported through theoretical studies the piezoelectric effect in BaTiO3, SmTiO3, and YFeO3. In this paper, we used the Douglas-Kroll-Hess (DKH) second-order scalar relativistic method to investigate the piezoelectricity in YTiO3. In the calculations we used the [6s4p] and [10s5p4d] Gaussian basis sets for the O (3P) and Ti (5S) atoms, respectively, from the literature in combination with the (30s21p16d)/[15s9p6d] basis set for the Y (3D) atom, obtained by generator coordinate Hartree-Fock (GCHF) method, and they had their quality evaluated using calculations of total energy and orbital energies (HOMO and HOMO-1) of the 2TiO+1 and 1YO+1 fragments. The dipole moment, the total energy, and the total atomic charges in YTiO3 in Cs space group were calculated. When we analyze those properties we verify that it is reasonable to believe that YTiO3 does not present piezoelectric properties.

scholarly journals Adapted Gaussian basis sets for atoms from Li through Xe generated with the generator coordinate Hartree-Fock method

2001 ◽  
Vol 73 (4) ◽  
pp. 511-517 ◽  
Author(s):  
EUSTÁQUIO V. R. DE CASTRO ◽  
FRANCISCO E. JORGE
Keyword(s):  
Total Energy ◽  
Wave Functions ◽  
Basis Sets ◽  
Gaussian Basis Sets ◽  
Hartree Fock ◽  
Generator Coordinate ◽  
Discretization Technique

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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