ISSN:
0192-8651
Keywords:
Computational Chemistry and Molecular Modeling
;
Biochemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Computer Science
Notes:
Ab initio calculations using both pseudopotential and double and triple-ζ all-electron basis sets, with and without electron correlation (MP2, QCISD), have been performed on the λ4-sulfanyl (SH3), λ4-selanyl (SeH3), and λ4-tellanyl (TeH3) radicals. All-electron basis sets of double-ζ quality predict that SH3 and SeH3 correspond to transition states on their respective potential energy surfaces. In contrast, the pseudopotentials of Hay and Wadt predict that SH3 and SeH3 correspond to local minima at the QCISD level of theory while the pseudopotentials of Christiansen and Stevens predict transition states. By comparison, TeH3 proved to be a local minimum at all levels of theory. Interestingly, when a very large (triple-ζ) all-electron basis set was used, SH3 proved to be a transition state; however, in this instance the potential energy surface was found to be much flatter than in the case for which a double-ζ basis set was used, suggesting that further improvements in the basis set may lead to a local minimum. Further improvements in the all-electron selenium basis also led to a local minimum for SeH3 at the QCISD level of theory. © 1995 by John Wiley & Sons, Inc.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcc.540160902
