Knockout driven fragmentation of porphyrins

TL;DR

This study investigates how collisions with helium and neon cause fragmentation of porphyrins, revealing that prompt atom knockout significantly contributes to molecular destruction, with implications for understanding collision processes in biomolecules.

Contribution

It introduces a combined experimental and computational approach to isolate and analyze impulse-driven atom knockout in porphyrin collisions, a process previously difficult to observe.

Findings

Prompt atom knockout is a major factor in porphyrin destruction.

Collision energies of 50-110 eV induce significant fragmentation.

Impulsive processes lead to highly reactive fragments.

Abstract

We have studied collisions between tetraphenylporphyrin cations and He or Ne at center-of-mass energies in the 50-110 eV range. The experimental results were interpreted in view of Density Functional Theory calculations of dissociation energies and classical Molecular Dynamics simulations of how the molecules respond to He/Ne impact. We demonstrate that prompt atom knockout strongly contributes to the total destruction cross sections. Such impulse driven processes typically yield highly reactive fragments and are expected to be important for collisions with any molecular system in this collision energy range, but have earlier been very difficult to isolate for biomolecules.