Modeling the time-resolved Coulomb explosion imaging of halomethane photodissociation with \textit{ab initio} potential energy curves

Abstract

We present an effective theoretical model to simulate observables in time-resolved two-fragment Coulomb explosion experiments. The model employs the potential energy curves of the neutral molecule and the doubly charged cation along a predefined reaction coordinate to simulate the photodissociation process followed by Coulomb explosion. We compare our theoretical predictions with pump-probe experiments on iodomethane and bromoiodomethane. Our theory successfully predicts the two reaction channels in iodomethane photodissociation that lead to $\text{I}{(}^2{\text{P}}_{3/2})$ and ${\text{I}}^{\ast }{(}^2{\text{P}}_{1/2})$ products, showing excellent agreement with experimental delay-dependent kinetic energy release signals at large pump-probe delays. The theoretical kinetic energy release at small delays depends significantly on the choice of ionic states. By accounting for internal rotation, the kinetic energies of individual fragments in bromoiodomethane align well with experimental results. Furthermore, our theory confirms that two-fragment Coulomb explosion imaging cannot resolve different spin channels in bromoiodomethane photodissociation.

arXiv comment7 pages, 5 figures

References in corpus (5)

• Coulomb explosion imaging of concurrent CH${}_2$BrI photodissociation dynamics
• Probing the UV-Induced Photodissociation of CH${}_{\text{3}}$I and C${}_{\text{6}}$H${}_{\text{3}}$F${}_{\text{2}}$I with Femtosecond Time-Resolved Coulomb Explosion Imaging at FLASH
• Gas-phase structural isomer identification by Coulomb explosion of aligned molecules
• Differentiating Three-Dimensional Molecular Structures using Laser-induced Coulomb Explosion Imaging
• Surface hopping molecular dynamics simulation of ultrafast methyl iodide photodissociation mapped by Coulomb explosion imaging

Cited by in corpus (2)

• Ultrafast photodissociation dynamics of dichloromethane on three-dimensional potential energy surfaces and its Coulomb explosion signature
• Ground and low-lying excited state potential energy surfaces of diiodomethane in four dimensions