Empirical Corrections of Scf Geometries with Special Examples from 4-21g Calculations
by de Smedt, Jef; Vanhouteghem, Frankie; Van Alsenoy, Christian; Geise, Herman J.; Schäfer, Lothar
Two approaches are compared, one using individual empirical corrections for parameter types defined in agreement with chemical intuition, and one using a linear regression of the type r(g)(calc) = a r(e)(ab initio) + b, to correct C-X bond lengths (X = C, N, 0 or F) calculated at the SCF/4-21G level. The regression lines obtained from SCF calculations using various basis sets (4-21G, 6-31G and 6-31G**) show no significant differences in applicability and the slopes of all of them are in contrast to well known physical effects.
- Journal of Molecular Structure-Theochem
- Start Page
- 2210-2728; 0166-1280