Phys. Chem. Chem. Phys. 24, 5343 (2022)

Shells in CO₂ clusters

John W. Niman^a, Benjamin S. Kamerin^a, Vitaly V. Kresin^a, Jan Krohn^b, Ruth Signorell^b, Roope Halonen^c, and Klavs Hansen^*,c,d 

a Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484, USA

b Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog Weg 2, CH-8093 Zürich, Switzerland

c Center for Joint Quantum Studies and Department of Physics, School of Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China

d Lanzhou Center for Theoretical Physics, Key Laboratory of Theoretical Physics of Gansu Province, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China

* Corresponding authors ( klavshansen@tju.edu.cn )

Abstract

Abundance spectra of (CO₂)_N clusters up to N ≈ 500 acquired under a wide range of adiabatic expansion conditions are analyzed within the evaporative ensemble framework. The analysis reveals that the cluster stability functions display a strikingly universal pattern for all expansion conditions. These patterns reflect the inherent properties of individual clusters. From this analysis the size-dependent cluster binding energies are determined, shell and subshell closing sizes are identified, and cuboctahedral packing ordering for sizes above N ≈ 130 is confirmed. It is demonstrated that a few percent variation in the dissociation energies translates into significant abundance variations, especially for the larger clusters.