Selectivity of weak intermolecular forces and precursor state of elementary oxidation reactions, a new insight on Ne* + N2 chemiionization

This paper reports on the collision dynamics of N2 with metastable Ne* promoting chemiionizations, prototype of barrier-less oxidation reactions of great interest for fundamental and applied research. Extending guidelines presented in previous papers for the atom–atom case, an innovative treatment of the reaction stereodynamics involving molecules in a quantum state-to-state resolution conditions is proposed that emphasizes the role of structure and stability of the precursor that is here the reaction transition state. A critical test of such treatment, carried out exploiting a new formulation both of real and imaginary parts of the optical potential driving the reaction dynamics, is represented by the detailed-combined description of all relevant findings, provided by high resolution molecular beam scattering experiments carried out in our and other laboratories. The present analysis casts light on basic electronic rearrangements of such prototype oxidation reaction which are expected to be of fundamental interest for many other reactions involving open shell atoms and free radicals.

The Halogen-Bond Nature in Noble Gas–Dihalogen Complexes from Scattering Experiments and Ab Initio Calculations

In order to clarify the nature of the halogen bond (XB), we considered the prototype noble gas–dihalogen molecule (Ng–X2) systems, focusing on the nature, range, and strength of the interaction. We exploited data gained from molecular beam scattering experiments with the measure of interference effects to obtain a suitable formulation of the interaction potential, with the support of high-level ab initio calculations, and charge displacement analysis. The essential interaction components involved in the Ng–X2 adducts were characterized, pointing at their critical balance in the definition of the XB. Particular emphasis is devoted to the energy stability of the orientational Ng–X2 isomers, the barrier for the X2 hindered rotation, and the influence of the X2 electronic state. The present integrated study returns reliable force fields for molecular dynamic simulations in Ng–X2 complexes that can be extended to systems with increasing complexity and whose properties depend on the selective formation of XB.

The Halogen-Bond Nature in Noble Gas-Dihalogen Complexes from Scattering Experiments and Ab-Initio Calculations

In order to clarify the nature of the halogen bond (XB), we considered the prototype noble gas – dihalogen molecule (Ng-X2) systems, focusing on the nature, range and strength of the interaction. We exploited data gained from molecular beam scattering experiments with the measure of interference effects to obtain a suitable formulation of the interaction potential, with the support of high-level ab initio calculations, and charge displacement analysis. The essential interaction components involved in the Ng-X2 adducts have been characterized, pointing at their critical balance in the definition of the XB. Particular emphasis is devoted to the energy stability of the orientational Ng-X2 isomers, the barrier for the X2 hindered rotation, and the influence of the X2 electronic state. The present integrated study returns reliable force fields for molecular dynamics simulations in Ng-X2 complexes that can be extended to systems with increasing complexity and whose properties depend on the selective formation of XB.

Insight into the halogen-bond nature of noble gas-chlorine systems by molecular beam scattering experiments, ab initio calculations and charge displacement analysis

A weak halogen bond, together with charge transfer from a noble gas to Cl2, characterizes the intermolecular interaction between a noble gas atom and Cl2 in a collinear configuration.