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Updated: Nov 6, 2025
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Role of Dynamical Electron Correlation in the Differences in Bonding between CaAlH3 and MgAlH3
Fabio E Penotti1, David L Cooper2, Peter B Karadakov3
1Consiglio Nazionale delle Ricerche Istituto di Scienze e Tecnologie Chimiche "Giulio Natta", Via Golgi 19, I-20133 Milano, MI, Italy.
Abstract:
The most important factor behind the intriguing differences between the geometries of the M'AlH3 (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.
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