ISSN:
0020-7608
Keywords:
Computational Chemistry and Molecular Modeling
;
Atomic, Molecular and Optical Physics
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A detailed investigation has been made of the methodological dependence of computed structures, binding energies, and some vibrational properties of selected hydrogen-bonded complexes. Structures and vibrational frequencies have been computed using four different levels of theory: HF/6-31G(d), HF/6-31+G(d, p), MP2/6-31G(d), and MP2/6-31+G(d, p). Correlation energy effects on computed binding energies and the basis set dependence of these energies have been evaluated using the Dunning correlation-consistent polarized valence double-, triple-, and truncated quadruple-split basis sets (cc-pVXZ, with X = D for double, T for triple, and Q́ for truncated quadruple), and these same basis sets augmented with diffuse functions on nonhydrogen atoms (cc-pVXZ+). The results of these studies suggest that the methodology of MBPT(4) = MP4/cc-pVTZ+ electronic energies without the counterpoise correction computed at MP2/6-31+G(d, p) geometries is an appropriate theoretical model for investigating complexes RCN ⃛ HX, with R = H or CH3 and X = F or Cl. This model has been applied to investigate the structures, binding energies at absolute zero, binding enthalpies at room temperature, and vibrational frequencies of these complexes. Trends are noted, and comparisons are made with available experimental data. © 1992 John Wiley & Sons, Inc.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560440848
