Estudo ab-initio da a-alanina em meio aquoso


Autoria(s): Sambrano, Julio Ricardo; Souza, Aguinaldo Robinson de; Queralt, Joaquim Josep; Andrés, Juan; Longo, Elson
Contribuinte(s)

Universidade Estadual Paulista (UNESP)

Data(s)

20/05/2014

20/05/2014

01/07/1999

Resumo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ab initio Hartree-Fock (HF), Density Functional (B3LYP) and electron correlation (MP2) methods have been used to caracterize the aqueous medium intramolecular hydrogen bond in a-alanine. The 6-31G* and 6-31++G** were taken from Gaussian94 library. We were concerned on the structure of three conformers of a-alanine, in their neutral form plus on the structure of the zwitterionic form (Z). The Z structure is a stationary point at the HF/6-31G* level but it is not when diffuse functions and electron correlation are included. This results shows that the Z form does not exist in the gas phase. The inclusion of solvent effects changed significantly the results obtained in gas phase, therefore this inclusion make the Z form a stationary point within all level of theory, and the relative energy depends dramatically on the level of calculation.

Formato

501-505

Identificador

http://dx.doi.org/10.1590/S0100-40421999000400006

Química Nova. Sociedade Brasileira de Química, v. 22, n. 4, p. 501-505, 1999.

0100-4042

http://hdl.handle.net/11449/27562

10.1590/S0100-40421999000400006

S0100-40421999000400006

WOS:000081587600006

2-s2.0-0004631658

Idioma(s)

por

Publicador

Sociedade Brasileira de Química

Relação

Química Nova

Direitos

openAccess

Palavras-Chave #ab initio #a-alanine #solvent
Tipo

info:eu-repo/semantics/article