Crystal Structure and Theoretical Analysis of Green Gold Au30(S‑tBu)18 Nanomolecules and Their Relation to Au30S(S‑tBu)18

• Published in: Journal of physical chemistry. C 2016-03, Vol.120 (11), p.6256-6261
• Main Authors: Dass, Amala, Jones, Tanya, Rambukwella, Milan, Crasto, David, Gagnon, Kevin J, Sementa, Luca, De Vetta, Martina, Baseggio, Oscar, Aprà, Edoardo, Stener, Mauro, Fortunelli, Alessandro
• Format: Article
• Language: English
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.6b00062

We report the complete X-ray crystallographic structure as determined through single-crystal X-ray diffraction and a thorough theoretical analysis of the green gold Au30(S-tBu)18. While the structure of Au30S­(S-tBu)18 with 19 sulfur atoms has been reported, the crystal structure of Au30(S-tBu)18 without the μ3-sulfur has remained elusive until now, though matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) and electrospray ionization mass spectrometry (ESI-MS) data unequivocally show its presence in abundance. The Au30(S-tBu)18 nanomolecule not only is distinct in its crystal structure but also has unique temperature-dependent optical properties. Structure determination allows a rigorous comparison and an excellent agreement with theoretical predictions of structure, stability, and optical response.