We studied the nature of the interaction of the weakly bound BeHe adduct by means of an integrated theoretical approach based on high-level quantum chemical calculations for the characterization of the potential energy surfaces and charge displaced upon adduct formation, together with the development of a semi-empirical analytical formulation of the interaction potential. Our results show that Be is able to form a stable adduct with He when the Be(1D) (1s2 2s2!1s2 2s0 2p2) excited state is involved, with a binding energy of as much as 10.2 kcal/mol, an astonishingly large value for He in neutral systems. The analysis of the leading interaction components in the Be*He adduct proves the relevance of the charge transfer to the overall stability, which contributes to decreasing the intermolecular distance, thus strengthening the induction-energy component.
Modelling Charge Transfer in Weak Chemical Bonds: Insights from the Chemistry of Helium
Nunzi, Francesca;Cesario, Diego;Pirani, Fernando;Tarantelli, Francesco
2018
Abstract
We studied the nature of the interaction of the weakly bound BeHe adduct by means of an integrated theoretical approach based on high-level quantum chemical calculations for the characterization of the potential energy surfaces and charge displaced upon adduct formation, together with the development of a semi-empirical analytical formulation of the interaction potential. Our results show that Be is able to form a stable adduct with He when the Be(1D) (1s2 2s2!1s2 2s0 2p2) excited state is involved, with a binding energy of as much as 10.2 kcal/mol, an astonishingly large value for He in neutral systems. The analysis of the leading interaction components in the Be*He adduct proves the relevance of the charge transfer to the overall stability, which contributes to decreasing the intermolecular distance, thus strengthening the induction-energy component.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
