Molecular van der Waals Fluids in Cavity Quantum Electrodynamics

John P Philbin; Tor S Haugland; Tushar K Ghosh; Enrico Ronca; Ming Chen; Prineha Narang; Henrik Koch

doi:10.1021/acs.jpclett.3c01790

Molecular van der Waals Fluids in Cavity Quantum Electrodynamics

J Phys Chem Lett. 2023 Oct 12;14(40):8988-8993. doi: 10.1021/acs.jpclett.3c01790. Epub 2023 Sep 29.

Authors

John P Philbin^{1

2}, Tor S Haugland³, Tushar K Ghosh⁴, Enrico Ronca^{5

6}, Ming Chen⁴, Prineha Narang^{1

2}, Henrik Koch^{3

7}

Affiliations

¹ Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.
² College of Letters and Science, University of California, Los Angeles, California 90095, United States.
³ Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
⁴ Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
⁵ Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto, 8, 06123 Perugia, Italy.
⁶ Max Planck Institute for the Structure and Dynamics of Matter and Center Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg, Germany.
⁷ Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56124 Pisa, Italy.

Abstract

Intermolecular van der Waals interactions are central to chemical and physical phenomena ranging from biomolecule binding to soft-matter phase transitions. In this work, we demonstrate that strong light-matter coupling can be used to control the thermodynamic properties of many-molecule systems. Our analyses reveal orientation dependent single molecule energies and interaction energies for van der Waals molecules. For example, we find intermolecular interactions that depend on the distance between the molecules R as R^-3 and R⁰. Moreover, we employ ab initio cavity quantum electrodynamics calculations to develop machine-learning-based interaction potentials for molecules inside optical cavities. By simulating systems ranging from 12 H₂ to 144 H₂ molecules, we observe varying degrees of orientational order because of cavity-modified interactions, and we explain how quantum nuclear effects, light-matter coupling strengths, number of cavity modes, molecular anisotropies, and system size all impact the extent of orientational order.