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Updated: Jul 19, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Towards chemical accuracy for the thermodynamics of large molecules: new hybrid density functionals including
Tobias Schwabe1, Stefan Grimme
1Theoretische Organische Chemie, Organisch-Chemisches Institut der Universität Münster, Corrensstrasse 40, D-48149, Münster, Germany.
Abstract:
Two hybrid density functionals that include a second-order perturbation correction for non-local correlation effects are tested for the full G3/05 test set. Very large AO basis sets including core-polarization/correlation functions have been employed that yield for the first time results quite close to the basis set limit for this set. The B2-PLYP functional and the new mPW2-PLYP approach with a modified exchange part give by far the lowest MAD over the whole G3/05 set ever reported for a DFT method (2.5 and 2.1 kcal mol(-1), respectively). The big improvement compared to common density functionals is further demonstrated by the reduction of the maximum and minimum errors (outliers) and by much smaller errors for complicated molecular systems.
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