Anchoring the water dimer potential energy surface with explicitly correlated computations and focal point analyses

Autor: Edward F. Valeev, Martin Quack, Brian C. Hoffman, Henry F. Schaefer, Matthew L. Leininger, Gregory S. Tschumper
Rok vydání: 2002
Předmět:
Zdroj: The Journal of Chemical Physics. 116:690-701
ISSN: 1089-7690
0021-9606
DOI: 10.1063/1.1408302
Popis: Ten stationary points on the water dimer potential energy surface have been characterized with the coupled-cluster technique which includes all single and double excitations as well as a perturbative approximation of triple excitations [CCSD(T)]. Using a triple-ζ basis set with two sets of polarization functions augmented with higher angular momentum and diffuse functions [TZ2P(f,d)+dif], the fully optimized geometries and harmonic vibrational frequencies of these ten stationary points were determined at the CCSD(T) theoretical level. In agreement with other ab initio investigations, only one of these ten stationary points is a true minimum. Of the other nine structures, three are transition structures, and the remaining are higher order saddle points. These high-level ab initio results indicate that the lowest lying transition state involved in hydrogen interchange is chiral, of C1 symmetry rather than Cs as suggested by recently developed 6D potential energy surfaces. The one- and n-particle limits of t...
Databáze: OpenAIRE