High-Accuracy ab Initio Rotation-Vibration Transitions for Water
Oleg L. Polyansky,1*
Attila G. Császár,2
Sergei V. Shirin,3
Nikolai F. Zobov,3
Paolo Barletta,1
Jonathan Tennyson,1
David W. Schwenke,4
Peter J. Knowles5
The spectrum of water vapor is of fundamental
importance for a variety of processes, including the absorption and
retention of sunlight in Earth's atmosphere. Therefore, there has long
been an urgent need for a robust and accurate predictive model for this
spectrum. In our work on the high-resolution spectrum of water, we
report first-principles calculations that approach experimental accuracy. To achieve this, we performed exceptionally large electronic structure calculations and considered a variety of effects, including quantum electrodynamics, which have routinely been neglected in studies
of small many-electron molecules. The high accuracy of the resulting ab
initio procedure is demonstrated for the main isotopomers of water.
1 Department of Physics and Astronomy,
University College London, Gower Street, London WC1E 6BT, UK.
2 Department of Theoretical Chemistry,
Eötvös Loránd University, H-1518 Budapest 112, Post
Office Box 32, Hungary.
3 Institute of Applied
Physics, Russian Academy of Sciences, Uljanov Street 46, Nizhnii
Novgorod, Russia 603950.
4 NASA Ames Research
Center, Moffett Field, CA 94035-1000, USA.
5 School
of Chemical Sciences, University of Birmingham, Birmingham B15
2TT, UK.
*
Present address: Institute of Applied Physics, Russian Academy
of Sciences, Uljanov Street 46, Nizhnii Novgorod, Russia 603950.
To whom correspondence should be addressed. E-mail:
j.tennyson{at}ucl.ac.uk