Clusters containing open-shell molecules. II. Equilibrium structures of ArnOH Van der Waals clusters (X2Π, n=1 to 15)

Xu, M. Z.; Bačić, Z.; Hutson, J. M.

Abstract

The equilibrium and low-lying isomeric structures of ArnOH (X2Π)clusters for n=1 to 15 are investigated by simulated annealing calculations. Potential energy surfaces are obtained by a pairwise-additive approach, taking into account the open-shell nature of OH X2Π and including spin-orbit coupling. It is found that the spin-orbit coupling suppresses the Jahn–Teller effect, and many of the clusters have high-symmetry structures(Cnν with n>2) which would be forbidden in the absence of spin-orbit coupling. The structures are generally similar to those previously found for the closed-shell systems ArnHF and ArnHCl, but different from those for the open-shell systems ArnNO and ArnCH. This is because Ar–OH (X2Π), like Ar–HF and Ar–HCl but unlike Ar–NO and Ar–CH, has a near-linear equilibrium structure.ArnOHclusters for n up to 6 have all Ar atoms in a single shell around OH. In the clusters with n=7 to 9, OH is under a pentagonal pyramid formed by six Ar atoms, while the others bind to its exterior, away from OH. For n=10 to 12, the minimum-energy structures have OH inside an Arn cage, which is essentially icosahedral for n=12 but has vacancies for n=10 and 11. For n>12, the extra Ar atoms begin to form a second solvation shell. The global minimum of ArnOH may be constructed from the minimum-energy structure of Arn+1 by replacing one Ar atom with OH.

Citation

Xu, M. Z., Bačić, Z., & Hutson, J. M. (2002). Clusters containing open-shell molecules. II. Equilibrium structures of ArnOH Van der Waals clusters (X2Π, n=1 to 15). The Journal of Chemical Physics, 117(10), 4777-4786. https://doi.org/10.1063/1.1497966

• Journal Article Type: Article
• Publication Date: Sep 8, 2002
• Deposit Date: Aug 19, 2015
• Publicly Available Date: Aug 19, 2015
• Journal: Journal of Chemical Physics
• Print ISSN: 0021-9606
• Electronic ISSN: 1089-7690
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 117
• Issue: 10
• Pages: 4777-4786
• DOI: https://doi.org/10.1063/1.1497966
• Public URL: https://durham-repository.worktribe.com/output/1600230