Abstract
This work presents a systematic investigation into the basis set convergence of harmonic vibrational frequencies of (H2O)2 and (HF)2 computed with second-order Møller-Plesset perturbation theory (MP2) and the coupled-cluster singles and doubles method with perturbative connected triples, CCSD(T), while employing correlation-consistent basis sets as large as aug-cc-pV6Z. The harmonic vibrational frequencies presented here are expected to lie within a few cm-1 of the complete basis set (CBS) limit. For these important hydrogen-bonding prototype systems, a basis set of at least quadruple-ζ quality augmented with diffuse functions is required to obtain harmonic vibrational frequencies within 10 cm-1 of the CBS limit. In addition, second-order vibrational perturbation theory (VPT2) anharmonic corrections yield CCSD(T) vibrational frequencies in excellent agreement with experimental spectra, differing by no more than a few cm-1 for the intermonomer fundamental vibrations. D0 values predicted by CCSD(T) VPT2 computations with a quadruple-ζ basis set reproduce the experimental values of (HF)2 and (H2O)2 to within 2 and 21 cm-1, respectively. (Chemical Presented).
Recommended Citation
J. C. Howard et al., "Getting Down to the Fundamentals of Hydrogen Bonding: Anharmonic Vibrational Frequencies of (Hf)2 and (H2o)2 from Ab Initio Electronic Structure Computations," Journal of Chemical Theory and Computation, vol. 10, no. 12, pp. 5426 - 5435, American Chemical Society, Dec 2014.
The definitive version is available at https://doi.org/10.1021/ct500860v
Department(s)
Chemistry
Publication Status
Open Access
International Standard Serial Number (ISSN)
1549-9626; 1549-9618
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 American Chemical Society, All rights reserved.
Publication Date
09 Dec 2014
Comments
National Science Foundation, Grant CHE-1156713