Open AccessRole of Dynamical Electron Correlation in the Differences in Bonding between CaAlH3 and MgAlH3
Author(s) -
Fabio E. Penotti,
David L. Cooper,
Peter B. Karadakov
Publication year - 2021
Publication title -
the journal of physical chemistry. a/the journal of physical chemistry. a.
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.756
H-Index - 235
eISSN - 1520-5215
pISSN - 1089-5639
DOI - 10.1021/acs.jpca.1c02422
Subject(s) - correlation , statistical physics , materials science , mathematics , physics , geometry
The most important factor behind the intriguing differences between the geometries of the M'AlH 3 (M' = Mg, Ca) molecules is shown to be dynamical electron correlation and not intramolecular Coulombic interactions, as previously thought. Spin-coupled generalized valence bond (SCGVB) calculations reveal the different bonding situations in the two molecules at their optimal geometries but do not explain why these geometries differ so much; the solution to this conundrum comes instead from detailed analysis of coupled-cluster (CCSD(T)) energies at model and optimal geometries.