- Award ID(s):
- NSF-PAR ID:
- Date Published:
- Journal Name:
- The Journal of Physical Chemistry A
- Page Range / eLocation ID:
- 1279 to 1291
- Medium: X
- Sponsoring Org:
- National Science Foundation
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The optimized geometries, vibrational frequencies, and dissociation energies from MP2 and CCSD(T) computations with large correlation consistent basis sets are reported for (H2S)2and H2O/H2S. Anharmonic vibrational frequencies have also been computed with second‐order vibrational perturbation theory (VPT2). As such, the fundamental frequencies, overtones, and combination bands reported in this study should also provide a useful road map for future spectroscopic studies of the simple but important heterogeneous H2O/H2S dimer in which the hydrogen bond donor and acceptor can interchange, leading to two unique minima with very similar energies. Near the CCSD(T) complete basis set limit, the HOH⋯SH2configuration (H2O donor) lies only 0.2 kcal mol−1below the HSH⋯OH2structure (H2S donor). When the zero‐point vibrational energy is included, however, the latter configuration becomes slightly lower in energy than the former by <0.1 kcal mol−1. © 2018 Wiley Periodicals, Inc.
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