Generator Coordinate
Mostrando 1-12 de 13 artigos, teses e dissertações.
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1. Estudo de um formalismo para discretizar eficientemente as equações integrais do Método da Coordenada Geradora Hartree-Fock / The study of a formalism to discretize efficiently the integral equations of the generator coordinate Hartree-Fock method
The search for high quality basis set is made by several groups since the quality of the basis sets is a very important factor to obtain accurate results for atomic and molecular properties. The basis sets used in this work are designed by using the polynomial Generate Coordinate Method and were constructed with the aim to improve the flexibility of a basis
Publicado em: 2009
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2. Aplicação de uma nova proposta de discretização das equações Griffin-Wheeler-Hartree-Fock na geração de bases Gaussianas para cálculos de átomos e moléculas / Aplication of a new proposal for the discretization of the Griffin-Wheeler-Hartree-Fock equations in the generation of Gaussian leases for atomic and molecular calculations
The ongoing evolution of computers has led to several changes in the way of doing science, to create a multitude of new options for solving scientific problems. The implementation of computational methods allowed the theoretical treatment of large systems, complex and different areas of science. One area of particular focus and chemistry of molecules, now ca
Publicado em: 2009
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3. The generator coordinate method in density-functional theory / O uso do método da coordenada geradora na teoria do funcional da densidade
Esta tese apresenta uma nova aproximação variacional baseada no Método da Coordenada Geradora e na Teoria do Funcional da Densidade. Nesta nova aproximação, a função de onda de muitos corpos é representada como uma superposição de determinantes de Slater Kohn-Sham não-ortogonais calculados a partir de Hamiltonianos diferentes que carregam uma coor
Publicado em: 2007
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4. Cálculos teóricos de afinidades por próton de n-alquilaminas usando o método ONIOM
The ONIOM method was used to calculate the proton affinities (PA) of n-alkylamines (CnH2n+1NH2, n = 3 to 6, 8, 10, 12, 14, 16 and 18). The calculations were carried out at several levels (HF, MP2, B3LYP, QCISD(T), ...) using Pople basis sets and at the QCISD(T) level using basis sets developed by the generator coordinate method (GCM) and adapted to effective
Química Nova. Publicado em: 2006-04
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5. Accurate Gaussian basis sets for the ground state of the CS molecule
Sequences of increasing size atom centered basis sets of Gaussian-type functions for the ground state of the CS molecule are generated with the molecular improved generator coordinate Hartree-Fock (HF) method. At the HF level, total and orbital energies and electric dipole moment and, at the second-order Mphiller-Plesset (MP2) level, correlation and dissocia
Brazilian Journal of Physics. Publicado em: 2005-12
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6. Analytical treatment for the deuteron-deuteron interaction
In the study of two interacting systems within the framework of microscopic theories, the correct treatment of the effective interaction between the fragments has been the most troubling problem, due to the technical difficulties in calculating the exchange terms. In the framework of the Generator Coordinate Method, and through a double projection technique,
Brazilian Journal of Physics. Publicado em: 2005-09
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7. Theoretical studyng of cross coupling mechanism presented in palladium-catalized Ph-Ph bond formation reaction by PhB (Oh)2 (Ph=C6H5) / Estudo teorico do mecanismo de acoplamento-cruzado envolvido na reação de formação da ligação Ph-Ph catalisada por paladio via PhB (OH)2 (Ph=C6H5)
By the generator coordinate method, atomic basis set function adapted to ECP-SBKJ was developed for B, C, N, O, F, P, S, CI e Pd using the functional B3LYP. The quality of these basis set function was tested by the determination of the proton affinity (PA) in such molecular models ( H, F, Cl, HO, HS, BH2, NH2, PH2, CH3, CH2F,CH2Cl, B(OH)2O, CH3O, CH3S, CH2FC
Publicado em: 2005
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8. Desenvolvimento teorico e computacional do modelo de matriz densidade aplicado ao metodo da coordenada geradora em calculos "ab initio" relativisticos / Theoretical and computational development of the relation between the generator coordinate method and density matrix theory applied to relativistic "ab initio" calculations
Este trabalho é uma contribuição ao estudo do problema da construção de conjuntos de base para cálculos "ab initio" relativísticos. Para tanto, tratamos aqui desde a etapa de obtenção de funções primitivas em nível SCF e correlacionado até a avaliação das mesmas em cálculos moleculares envolvendo diatômicas do bloco p. As metodologias utiliz
Publicado em: 2005
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9. Adapted Gaussian basis sets for atoms from Li through Xe generated with the generator coordinate Hartree-Fock method
Utiliza-se o método coordenada geradora Hartree-Fock para gerar bases Gaussianas adaptadas para os átomos de Li (Z=3) até Xe (Z=54). Neste método, integram-se as equações de Griffin-Hill-Wheeler-Hartree-Fock através da técnica de discretização integral. Comparam-se as funções de ondas geradas neste trabalho com as funções de ondas Roothaan-Hart
Anais da Academia Brasileira de Ciências. Publicado em: 2001-12
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10. Estudo da adsorção de hidrogênio e sulfeto na superfície de paládio: aspectos experimentais (eletroquímica) e teóricos (ab initio e Teoria do Funcional da Densidade)
The adsorption of H and S2- species on Pd (100) has been studied with ab initio, density-functional calculations and electrochemical methods. A cluster of five Pd atoms with a frozen geometry described the surface. The computational calculations were performed through the GAUSSIAN94 program, and the basis functions adapted to a pseudo-potential obtained by u
Química Nova. Publicado em: 2001-08
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11. Estudo teorico de equilibrios tautomericos contendo C e Si como atomos centrais averiguando-se efeitos de substituintes na afinidade por protons atraves de caculos teoricos ab initio e funcional de densidade
Theoretical study (ab initio and density functional) of the effects to different substituents, in tautomeric equilibrium:CH3(Y=O)CH2-X - CH3(Y-OH)=CH-X, with X = H, CH3, Cl, F, NH2 or OH and Y = C or Si. The analysis was carried out throught calculation of electronic properties: energy, molecular geometry and proton affinity. The basis sets used in the descr
Publicado em: 2000
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12. Desenvolvimento de funções de base GTO : aplicação de metodo da coordenada geradora atraves da tecnica de discretização integral otimizada
A systematic approach to obtaining GTO basis sets from atomic calculations at the Hartree-Fock leveI, employing the principIes of the Generator Coordinate Method (GCM) and the Optimized Integral Discretization technique (OID) is proposed. The discussion is centered on the formulation of a finite discretized space of GTO functions. Special attention is paid t
Publicado em: 1992