Work

Chirped-pulse Fourier transform microwave spectrum of the HCl–DCl heterodimer

Year: 2025

Type: article

Abstract: Hydrohalic acid dimers provide a fundamental opportunity to study hydrogen bond rearrangement dynamics at a high level of detail. The (HCl)2 and (DCl)2 homodimers do not have a pure rotational spectrum due to rapid geared tunneling motions that interchange the role of the hydrogen bond donor and acceptor. In this work, we report the pure rotational spectrum of HCl-DCl, which has a preference for deuterium in the hydrogen bond donor position. However, the quadrupole coupling constants indicate a significant amount of geared tunneling, consistent with significant zero-point wavefunction amplitude in the less stable DCl-HCl configuration. A comparison of experimental results with previously published wavefunction calculations based on model and ab initio potentials is consistent with a picture in which about 14% of the probability density distribution is located in the less stable well.

Source: The Journal of Chemical Physics

DOI: 10.1063/5.0273758

Authors: Muhammad Qasim Ali, Arun Bhujel, Salma Akter, Fan Xie, Melanie Schnell, G. Barratt Park

Institutions: Texas Tech University, Deutsches Elektronen-Synchrotron DESY, Christian-Albrechts-Universität zu Kiel, Max Planck Institute for Multidisciplinary Sciences

Language: English

Topic: Molecular Spectroscopy and Structure

Subfield: Spectroscopy

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funder: National Science Foundation

Award: CAREER: Tiny Drops of Acid: Microwave Spectroscopy and Isomer-resolved IR Spectroscopy of Hydrohalic Acid-Water Clusters