Coulomb explosion imaging of concurrent CH$_{2}$BrI photodissociation dynamics

TL;DR

This study uses time-resolved Coulomb explosion imaging to investigate the ultrafast photodissociation dynamics of CH$_{2}$BrI, revealing sequential bond cleavages and energy distribution in real-time.

Contribution

It demonstrates the application of Coulomb explosion imaging to monitor real-time molecular dissociation pathways and energy partitioning.

Findings

C-I bond cleavage occurs with 65.6% energy into internal states.

Second UV photon induces C-Br bond breaking.

Method confirms previous data at different wavelengths.

Abstract

The dynamics following laser-induced molecular photodissociation of gas-phase CH$_{2}$BrI at 271.6 nm were investigated by time-resolved Coulomb explosion imaging using intense near-IR femtosecond laser pulses. The observed delay-dependent photofragment momenta reveal that CH$_{2}$BrI undergoes C-I cleavage, depositing 65.6% of the available energy into internal product states, and that absorption of a second UV photon breaks the C-Br bond of CH$_{2}$Br. Simulations confirm that this mechanism is consistent with previous data recorded at 248 nm, demonstrating the sensitivity of Coulomb explosion imaging as a real-time probe of chemical dynamics.