High-accuracy ab initio rotation-vibration transitions for water.

Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK.
Science (Impact Factor: 31.48). 02/2003; 299(5606):539-42. DOI: 10.1126/science.1079558
Source: PubMed

ABSTRACT 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.

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