Electronic Coherences in Molecules: The Projected Nuclear Quantum Momentum as a Hidden Agent

TL;DR

This paper reveals the importance of projected nuclear quantum momenta in understanding electronic coherences in molecules, demonstrating that exact-factorization methods accurately capture these effects and improve the modeling of photo-induced molecular dynamics.

Contribution

It introduces the concept of projected nuclear quantum momenta as a key factor in electronic coherence and shows how exact-factorization methods effectively incorporate these correlations.

Findings

Exact-factorization methods accurately reproduce electronic coherences.

Projected nuclear quantum momenta are essential for correct coherence behavior.

Spatial dependence of coherences influences subsequent electron dynamics.

Abstract

Electronic coherences are key to understanding and controlling photo-induced molecular transformations. We identify a crucial quantum-mechanical feature of electron-nuclear correlation, the projected nuclear quantum momenta, essential to capture the correct coherence behavior. In simulations, we show that, unlike traditional trajectory-based schemes, exact-factorization-based methods approximate these correlation terms, and correctly capture electronic coherences in a range of situations, including their spatial dependence, an important aspect that influences subsequent electron dynamics and that is becoming accessible in more experiments.