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Updated: Jun 2, 2026
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Gas-phase and Ar-matrix SQM scaling factors for various DFT functionals with basis sets including polarization and
Csaba Fábri1, Tamás Szidarovszky, Gábor Magyarfalvi
1Laboratory of Molecular Spectroscopy, Institute of Chemistry, Eötvös University, Budapest, Hungary.
Abstract:
Scaling factors for Pulay's scaled quantum mechanical (SQM) scheme have been determined for four different widely used DFT functionals (PBE, B3LYP, B3PW91, and M06-2X) and for two basis sets (6-31++G** and aug-cc-pVTZ) by fitting computed results to 347 fundamental experimental vibrational frequencies of 33 molecules. Measurements in the gas phase and in solid argon matrices were used independently in the fitting procedure in order to provide a simple method of estimating matrix shifts. The accuracy of the new scaling factors is demonstrated on test molecules including hydrogen-bonded systems and molecules containing chlorine and sulfur atoms.
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