Transferability of pairwise atom potential parameters a test on the structural calculation of the glyoxal Ar complex isomers

Autor: Luc Lapierre, Paul DeROSE, Hai-Lung Dai
Rok vydání: 1996
Předmět:
Zdroj: Molecular Physics. 89:1223-1244
ISSN: 1362-3028
0026-8976
DOI: 10.1080/002689796173147
Popis: The pairwise atom potential approach for calculating intermolecular potential energy surfaces is tested on the glyoxal–Ar complex with three isomeric structures Potential parameters of the Ar–H, Ar–C and Ar–O pairs were extracted from fittings to the experimentally determined H2–Ar and CO2–Ar potential surfaces It is found that when an anisotropic term reflecting the π electron distribution in the CO chromophore is added the pair potential calculation can generate three potential minima with reasonable energies and van der Waals stretching frequencies mimicking the three experimentally observed structures The electronically excited complex parameters extracted from an ab initio calculation done for H2CO(A)–Ar can predict the shift of the Ar position upon electronic excitation of glyoxal These observations indicate the transferability of properly determined pair potential parameters from one molecular system to another and the importance of anisotropy which reflects the electron density spatial distributio...
Databáze: OpenAIRE