First-principles prediction and partial characterization of the vibrational states of water up to dissociation

Attila G. Császár, Edit Mátyus, Tamás Szidarovszky, Lorenzo Lodi, Nikolai F. Zobov, Sergei V. Shirin, Oleg L. Polyansky, Jonathan Tennyson

Research output: Article

61 Citations (Scopus)

Abstract

A new, accurate, global, mass-independent, first-principles potential energy surface (PES) is presented for the ground electronic state of the water molecule. The PES is based on 2200 energy points computed at the all-electron aug-cc-pCV6Z IC-MRCI(8,2) level of electronic structure theory and includes the relativistic one-electron mass-velocity and Darwin corrections. For H2 16O, the PES has a dissociation energy of D0 = 41109cm-1 and supports 1150 vibrational energy levels up to 41083cm-1. The deviation between the computed and the experimentally measured energy levels is below 15cm-1 for all the states with energies less than 39000cm-1. Characterization of approximate vibrational quantum numbers is performed using several techniques: energy decomposition, wave function plots, normal mode distribution, expectation values of the squares of internal coordinates, and perturbing the bending part of the PES. Vibrational normal mode labels, though often not physically meaningful, have been assigned to all the states below 26500cm-1 and to many more above it, including some highly excited stretching states all the way to dissociation. Issues to do with calculating vibrational band intensities for the higher-lying states are discussed.

Original languageEnglish
Pages (from-to)1043-1064
Number of pages22
JournalJournal of Quantitative Spectroscopy and Radiative Transfer
Volume111
Issue number9
DOIs
Publication statusPublished - jún. 1 2010

ASJC Scopus subject areas

  • Radiation
  • Atomic and Molecular Physics, and Optics
  • Spectroscopy

Fingerprint Dive into the research topics of 'First-principles prediction and partial characterization of the vibrational states of water up to dissociation'. Together they form a unique fingerprint.

  • Cite this