Prediction of Accurate Anharmonic Experimental Vibrational Frequencies for Water Clusters, (H2O)n, n = 2−5

Authors

George C. Shields, Bucknell UniversityFollow
Meghan E. Dunn
Timothy M. EvansFollow
Karl N. KirschnerFollow

Publication Date

2006

Description

Accurate anharmonic experimental vibrational frequencies for water clusters consisting of 2−5 water molecules have been predicted on the basis of comparing different methods with MP2/aug-cc-pVTZ calculated and experimental anharmonic frequencies. The combination of using HF/6-31G* scaled frequencies for intramolecular modes and anharmonic frequencies for intermolecular modes gives excellent agreement with experiment for the water dimer and trimer and are as good as the expensive anharmonic MP2 calculations. The water trimer, the cyclic C_i and S₄ tetramers, and the cyclic pentamer all have unique peaks in the infrared spectrum between 500 and 800 cm^-1 and between 3400 and 3700 cm^-1. Under the right experimental conditions these different clusters can be uniquely identified using high-resolution IR spectroscopy.

Journal

The Journal of Physical Chemistry

Volume

110

Issue

1

First Page

303

Last Page

309

Department

Chemistry

Link to Published Version

http://dx.doi.org/10.1021/jp054958y

Recommended Citation

Shields, George C.; Dunn, Meghan E.; Evans, Timothy M.; and Kirschner, Karl N.. "Prediction of Accurate Anharmonic Experimental Vibrational Frequencies for Water Clusters, (H2O)n, n = 2−5." The Journal of Physical Chemistry (2006) : 303-309.