Limited rotational and rovibrational line lists computed with highly accurate quartic force fields and ab initio dipole surfaces

• Quartic Force Fields (QFFs) yield highly accurate spectra including rotational structure.
• Infrared intensities (IR) are well determined using a CCSD(T) Dipole Moment Surface (DMS).
• Purely ab initio IR intensities agree extremely well with high-resolution experiment.
• Purely ab initio transition energies agree very well with high-resolution experiment.
• Ab initio purely rotational and rovibrational line lists should aid astronomers to assign lines.

In this work, computational procedures are employed to compute the rotational and rovibrational spectra and line lists for H2O, CO2, and SO2. Building on the established use of quartic force fields, MP2 and CCSD(T) Dipole Moment Surfaces (DMSs) are computed for each system of study in order to produce line intensities as well as the transition energies. The computed results exhibit a clear correlation to reference data available in the HITRAN database. Additionally, even though CCSD(T) DMSs produce more accurate intensities as compared to experiment, the use of MP2 DMSs results in reliable line lists that are still comparable to experiment. The use of the less computationally costly MP2 method is beneficial in the study of larger systems where use of CCSD(T) would be more costly.

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