Quick scheme for evaluation of atomic charges in arbitrary aluminophosphate sieves on the basis of electron densities calculated with DFT methods.
J Comput Chem
; 28(10): 1695-703, 2007 Jul 30.
Article
em En
| MEDLINE
| ID: mdl-17342708
ABSTRACT
It is demonstrated that unique and simple analytical functions are justified for the atomic charge dependences q of the T (T = Al, P) and O atoms of aluminophosphates (AlPOs) using DFT calculations with several basis sets, starting from STO-3G to 3-21G and 6-21G**. Three internal (bonds, angles, ...) coordinates for the charge dependences of the T atoms and four coordinates for the O are sufficient to reach a precision of 1.8% for the fitted q(Al), 1.0% for q(P), and 2.5% for q(O) relatively to the values calculated at any basis set level. The proposed strategy consists in an iterative scheme starting from charge dependences based on the neighbor's positions only. Electrostatic potential values are computed to illustrate the differences between the calculated and fitted charges in the considered AlPO models.
Buscar no Google
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2007
Tipo de documento:
Article