Vibrational anharmonic calculations in solution: performance of various DFT approaches
1Laboratoire de Chimie Théorique et Physico-Chimie Moléculaire, UMR 5624-Fédération de Recherche IPREM 2606, Université de Pau et des Pays de l'Adour, 64075 Pau Cedex, France. didier.begue@univ-pau.fr
Abstract:
We report anharmonic spectra calculated for formaldehyde in acetonitrile solution using the quartic force field obtained for various DFT/solvent coupled models. A statistical study has been carried out for each mode by using several classes of DFT functionals and comparing them to the reference ab-initio CCSD(T)/cc-pVQZ calculations. Results lead to the recommended use of hybrid functionals associated with the 6-31+G** basis set and the Polarized Continuum model (PCM) to predict the expected shifts relative to the gas phase.
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