RT Journal Article
T1 New approach for correcting noncovalent interactions in semiempirical quantum mechanical methods: the importance of multiple-orientation sampling
A1 Pérez Tabero, Sergio
A1 Fernández Rodríguez, Berta
A1 Cabaleiro Lago, Enrique Manuel
A1 Martínez Núñez, Emilio
A1 Vázquez Rodríguez, Saulo Ángel
K1 Interaction energies
K1 Molecules
K1 Noncovalent interactions
K1 Oligomers
K1 Organic acids
AB A new approach is presented to improve the performance of semiempirical quantum mechanical (SQM) methods in the description of noncovalent interactions. To show the strategy, the PM6 Hamiltonian was selected, although, in general, the procedure can be applied to other semiempirical Hamiltonians and to different methodologies. A set of small molecules were selected as representative of various functional groups, and intermolecular potential energy curves (IPECs) were evaluated for the most relevant orientations of interacting molecular pairs. Then, analytical corrections to PM6 were derived from fits to B3LYP-D3/def2-TZVP reference–PM6 interaction energy differences. IPECs provided by the B3LYP-D3/def2-TZVP combination of the electronic structure method and basis set were chosen as the reference because they are in excellent agreement with CCSD(T)/aug-cc-pVTZ curves for the studied systems. The resulting method, called PM6-FGC (from functional group corrections), significantly improves the performance of PM6 and shows the importance of including a sufficient number of orientations of the interacting molecules in the reference data set in order to obtain well-balanced descriptions
PB ACS Publications
SN 1549-9618
YR 2021
FD 2021
LK http://hdl.handle.net/10347/29036
UL http://hdl.handle.net/10347/29036
LA eng
NO J. Chem. Theory Comput. 2021, 17, 5556−5567. https://doi.org/10.1021/acs.jctc.1c00365
NO The authors thank financial support from Ministerio de Ciencia e Innovación (grant # PID2019-107307RB-I00) and Xunta de Galicia (ED431C 2021/40). We also thank CESGA for computational facilities
DS Minerva
RD 27 abr 2026