Towards an understanding of the vibrational spectrum of the neutral Au7cluster

Mancera, Luis A.; Benoit, David M.

Abstract

We present a detailed theoretical study of the vibrational spectrum of the neutral Au 7 cluster, aimed at understanding its reported experimental spectrum [P. Gruene et al., Science, 2008, 321, 674]. We study the effect of vibrational anharmonicity, polymorphism, noble gas embedding, and the use of various electronic-structure methods. We use a vibrational configuration- interaction approach (VCI) with a vibrational self-consistent field (VSCF) basis, in order to study the effect of vibrational anharmonicity for the density functional theory (DFT) global minimum energy structure. Our implementation of the VSCF/VCI method is based on the direct calculation of the potential energy surface (PES) using pseudo potential plane-wave DFT. An efficient reduction of the number of mode-mode couplings between vibrational modes (fast-VSCF/VCI) is used to speed up calculations. We show that the rather small anharmonicity does not account for the difference between harmonic and experimental frequencies and consequently for the large globa l scaling factor, reported by the authors of the experiment. Instead, the use of different electronic structure methods allows for a significant reduction of the scaling factor. We also show that krypton embedding does not significantly change the vibrational frequencies of the Au 7 cluster. © 2013 The Owner Societies.

Citation

Mancera, L. A., & Benoit, D. M. (2013). Towards an understanding of the vibrational spectrum of the neutral Au7cluster. Physical chemistry chemical physics : PCCP, 15(6), 1929-1943. https://doi.org/10.1039/c2cp43211k

• Journal Article Type: Article
• Acceptance Date: Nov 23, 2012
• Online Publication Date: Nov 28, 2012
• Publication Date: Feb 14, 2013
• Deposit Date: Oct 23, 2018
• Journal: Physical Chemistry Chemical Physics
• Print ISSN: 1463-9076
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 15
• Issue: 6
• Pages: 1929-1943
• DOI: https://doi.org/10.1039/c2cp43211k
• Public URL: https://hull-repository.worktribe.com/output/516607
• Publisher URL: https://pubs.rsc.org/en/Content/ArticleLanding/2013/CP/C2CP43211K