Potential energy surface, dipole moment surface and the intensity calculations for the 10 micron, 5 micron, and 3 micron bands of ozone

Abstract

Monitoring ozone concentrations in the Earth's atmosphere using spectroscopic methods is a major activity which undertaken both from the ground and from space. However there are long-running issues of consistency between measurements made at infrared (IR) and ultraviolet (UV) wavelengths. In addition, key O${}_3$ IR bands at 10 \muu, 5 \muu\ and 3 \muu\ also yield results which differ by a few percent when used for retrievals. These problems stem from the underlying laboratory measurements of the line intensities. Here we use quantum chemical techniques, first principles electronic structure and variational nuclear-motion calculations, to address this problem. A new high-accuracy \ai\ dipole moment surface (DMS) is computed. Several spectroscopically-determined potential energy surfaces (PESs) are constructed by fitting to empirical energy levels in the region below 7000 \cm\ starting from an \ai\ PES. Nuclear motion calculations using these new surfaces allow the unambiguous determination of the intensities of 10 \muu\ band transitions, and the computation of the intensities of 10 \muu\ and 5 \muu\ bands within their experimental error. A decrease in intensities within the 3 \muu\ is predicted which appears consistent with atmospheric retrievals. The PES and DMS form a suitable starting point both for the computation of comprehensive ozone line lists and for future calculations of electronic transition intensities

arXiv comment36 pages, 1 figure, 5 tables

References in corpus (4)

• High accuracy CO${}_2$ line intensities determined from theory and experiment
• A room temperature CO${}_2$ line list with ab initio computed intensities
• Potential Biosignatures in Super-Earth Atmospheres II. Photochemical Responses
• High accuracy water potential energy surface for the calculation of infrared spectra

Cited by in corpus (7)

• EXOPLINES: Molecular Absorption Cross-Section Database for Brown Dwarf and Giant Exoplanet Atmospheres
• A new spectroscopically-determined potential energy surface and \emph{ab initio} dipole moment surface for high accuracy HCN intensity calculations
• A variationally computed room temperature line list for AsH${}_3$
• Empirical normal intensity distribution for overtone vibrational spectra of triatomic molecules
• Use of the complete basis set limit for computing highly accurate ab initio dipole moments
• Determination of approximate quantum labels based on projections of the total angular momentum on the molecule-fixed axis
• Modelling Triatomic Biosignatures: Ozone and Isotopomers