Vibrational Quantum-State-Controlled Reactivity in the O2+ + C3H4 Reaction

TL;DR

This study demonstrates that vibrational excitation of O2+ can selectively activate reaction pathways in its interaction with C3H4 isomers, leading to controlled product formation and revealing quantum-state influence on reactivity.

Contribution

It provides the first direct evidence of vibrational-state-controlled reactivity in an ion-molecule reaction, highlighting the role of vibrational excitation in pathway selectivity.

Findings

Vibrational excitation influences product branching ratios.

C2O+ forms exclusively in excited-state reactions.

Vibrational control can activate specific reaction pathways.

Abstract

Quantum-state-controlled reactivity is a long-standing goal in the field of physical chemistry. In this work, we explore the vibrational-state-dependent behavior of the ion-molecule reaction between O2+ in distinct vibrational states and two isomers of C3H4, allene (H2C3H2) and propyne (H3C3H). While most products are formed regardless of the vibrational state of O2+, the branching ratios are influenced by vibrational excitation, and a new product, C2O+, appears exclusively in the excited-state reactions. This selective formation of C2O+ demonstrates that vibrational excitation can effectively activate a reaction pathway, providing direct evidence of quantum-state control in reactivity. These results represent an important step towards the goal of quantum-state-controlled chemistry in molecular systems.