Communication: THz absorption spectrum of the CO2-H2O complex: observation and assignment of intermolecular van der Waals vibrations

J Andersen; J Heimdal; D W Mahler; B Nelander; R Wugt Larsen

doi:10.1063/1.4867901

Communication: THz absorption spectrum of the CO2-H2O complex: observation and assignment of intermolecular van der Waals vibrations

J Chem Phys. 2014 Mar 7;140(9):091103. doi: 10.1063/1.4867901.

Authors

J Andersen¹, J Heimdal², D W Mahler¹, B Nelander², R Wugt Larsen¹

Affiliations

¹ Department of Chemistry, Technical University of Denmark, Kemitorvet 206, 2800 Kgs. Lyngby, Denmark.
² MAX-IV Laboratory, Lund University, P. O. Box 118, 22100 Lund, Sweden.

PMID: 24606346
DOI: 10.1063/1.4867901

Abstract

Terahertz absorption spectra have been recorded for the weakly bound CO2-H2O complex embedded in cryogenic neon matrices at 2.8 K. The three high-frequency van der Waals vibrational transitions associated with out-of-plane wagging, in-plane rocking, and torsional motion of the isotopic H2O subunit have been assigned and provide crucial observables for benchmark theoretical descriptions of this systems' flat intermolecular potential energy surface. A (semi)-empirical value for the zero-point energy of 273 ± 15 cm(-1) from the class of intermolecular van der Waals vibrations is proposed and the combination with high-level quantum chemical calculations provides a value of 726 ± 15 cm(-1) for the dissociation energy D0.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Carbon Dioxide / chemistry*
Hydrophobic and Hydrophilic Interactions
Quantum Theory
Terahertz Spectroscopy*
Vibration
Water / chemistry*

Substances

Water
Carbon Dioxide