Simulating Non‐Adiabatic Dynamics of Photoexcited Phenyl Azide: Investigating Electronic and Structural Relaxation en Route to the Formation of Phenyl Nitrene

Abstract

Excited state molecular dynamics simulations of the photoexcited phenyl azide have been performed. The semi‐classical surface hopping approximation has enabled an unconstrained analysis of the electronic and nuclear degrees of freedom which contribute to the molecular dissociation of phenyl azide into phenyl nitrene and molecular nitrogen. The significance of the second singlet excited state in leading the photodissociation has been established through electronic structure calculations, based on multiconfigurational schemes, and state population dynamics. The investigations on the structural dynamics have revealed the N − N bond separation to be accompanied by synchronous changes in the azide N − N − N bond angle. The 100 fs simulation results in a nitrene fragment that is electronically excited in the singlet manifold.