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:
For several van der Waals molecules, the results of ab initio intermolecular perturbation theory are compared with the simple Buckingham-Fowler model. A selection of dimers is studied, with emphasis on cases where the experimental structure is not reliably predicted by the hard-sphere electrostatic model. Cases are reported where the electrostatic term dominates, in agreement with the model: HF···HF, H3N···HF, N2O···HF, and H2CO··· HF; cases where the electrostatic term dominates but the molecular shapes are not well described by hard spheres: CO2···H2O and CIF···HF; and cases where there is a delicate balance between the electrostatic and other terms:H2O···HF, H2O···HCCH, CO2···HF, CO2···N, and CH3CN···HCN. It is concluded that, in general, the electrostatic interaction is central to the strength and orientation dependence of the forces between molecules and that the model provides a useful approximation to this interaction, while perturbation theory gives a more complete picture.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560290520
