We report anharmonic vibrational spectra (fundamentals, first overtones) for the F-(H2O) and F-(H2O)2 clusters computed at the MP2 and CCSD(T) levels of theory with basis sets of triple zeta quality. The anharmonic spectra obtained on the potential energy surfaces evaluated at the CCSD(T) level of theory are the first ones reported at a correlated level beyond MP2. We have found that the effect of basis set can be as large as 100 cm-1 for the fundamentals and >200 cm-1 for the first overtones whereas the effect of higher correlation at the CCSD(T) level of theory is much smaller (50 cm-1 or less) with respect to MP2. Our calculations are in agreement with the limited available set of experimental data for these systems and provide additional information that can guide further experimental studies.
Revised: March 2, 2004 |
Published: June 19, 2003
Citation
Chaban G.M., S.S. Xantheas, and R.B. Gerber. 2003.Anharmonic Vibrational Spectroscopy of the F-(H2O)n complexes, n=1, 2.Journal of Physical Chemistry A 107, no. 24:4952-4956.PNNL-SA-38113.