Work

A Gravitational-like Relationship of Dispersion Interactions is Exhibited by 40 Pairs of Molecules and Noble Gas Atoms

Year: 2024

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide We present computational results of many-body dispersion (MBD) interactions for 40 pairs of molecular and atomic species: hydrocarbons, silanes, corresponding fluorinated derivatives, pairs which have multiple H---H contacts between the molecules, as well as pairs having π–π interactions, and pairs of noble gases. The calculations reveal that the MBD stabilization energy ( E DISP,MBD ) obeys a global relationship, which is gravitational-like . It is proportional to the product of the masses of the two molecules ( M 1 M 2 ) and inversely proportional to the corresponding distances between the molecular centers-of-mass ( R COM-COM ) or the H---H distances of the atoms mediating the interactions of the two molecules ( R H–H ). This relationship reflects the interactions of instantaneous dipoles, which are formed by the ensemble of bonds/atoms in the interacting molecules. Using the D4-corrected dispersion energy ( E DISP,D4 ), which accounts for three-body interactions, we find that the E DISP,MBD and E DISP,D4 data sets are strongly correlated. Based on valence-bond modeling, the dispersion interactions occur primarily due to the increased contributions of the oscillating-ionic VB structures which maintain favorable electrostatic interactions; the [Sub─C +:H –+ H:C – ─Sub] and [Sub─C: –+ H – H:C + ─Sub] structures; Sub symbolizes general residues. This augmented contribution is complemented by simultaneously diminished-weights of the destabilizing pair of structures, [Sub─C +:H –– H:C + ─Sub] and [Sub─:C – H ++ H:C – ─Sub]. The local charges are propagated to the entire ensemble of bonds/atoms by partially charging the Sub residues, thus bringing about the “gravitational-like” dependence of dispersion.

Source: Journal of the American Chemical Society

DOI: 10.1021/jacs.4c11211

Authors: David Danovich, Alexandre Tkatchenko, Santiago Alvarez, Sason Shaik

Institutions: Hebrew University of Jerusalem, University of Luxembourg, Universitat de Barcelona

Language: English

Topic: Advanced Chemical Physics Studies

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,500

Funders: Ministerio de Ciencia, Innovación y Universidades, Generalitat de Catalunya, Agència de Gestió d'Ajuts Universitaris i de Recerca