Non-adiabatic theory of the hydrogen bond. Quantum computation?

TL;DR

This paper introduces a non-adiabatic quantum mechanical framework for understanding hydrogen bonds, emphasizing coupled electronic and vibrational motions, offering a new perspective on proton tunnelling beyond traditional models.

Contribution

It presents a novel non-adiabatic Hamiltonian formalism that couples electronic and vibrational motions to better describe hydrogen bonds and proton tunnelling.

Findings

Supports the non-adiabatic approach with quasi-degeneracy evidence

Provides an alternative view of proton tunnelling

Challenges the traditional double-well potential model

Abstract

The hydrogen bond is usually described within the clamped nucleus approximation in which electronic and vibrational motions are considered separately. This approach leads to a double-well potential which facilitates proton tunnelling. In this work, the hydrogen bond is described by a formalism based on the non-adiabatic Hamiltonian in which electronic and vibrational motions are coupled. Quasi-degeneracy associated with the hydrogen bond supports this approach which is shown to afford an alternative picture of proton tunnelling.