Probing the structures and bonding of auropolyynes, Au-(C≡C) n -Au - ( n = 1-3), using high-resolution photoelectron imaging

• Published in: The Journal of chemical physics Vol. 149; no. 14; p. 144307
• Main Authors: León, Iker, Ruipérez, Fernando, Ugalde, Jesus M, Wang, Lai-Sheng
• Format: Journal Article
• Language: English
• Published: United States 14.10.2018
• ISSN: 1089-7690
• DOI: 10.1063/1.5040336

We report an investigation of a series of auropolyynes, Au-(C≡C) -Au ( = 1-3), using high-resolution photoelectron imaging and calculations. Vibrationally resolved photoelectron spectra are obtained, allowing the electron affinities of Au-(C≡C) -Au to be accurately measured as 1.651(1), 1.715(1), and 1.873(1) eV for = 1-3, respectively. Both the Au-C symmetric stretching and a bending vibrational frequency are observed for each neutral auropolyyne. Theoretical calculations find that the ground state of Au C has a linear acetylenic Au-C≡C-Au structure, whereas the asymmetric Au-Au-C≡C structure is a low-lying isomer. However, for Au C and Au C , our calculations show that the asymmetric Au-Au-(C≡C) isomers are the global minima and the Au-(C≡C) -Au symmetric structures become low-lying isomers. All the asymmetric Au-Au-(C≡C) isomers are found computationally to have much higher electron binding energies and are not accessible at the detachment photon energies used in the current study. For neutral Au C , the Au-(C≡C) -Au auropolyyne structures are found to be the global minima for = 1-3. The electronic structures and bonding for Au-(C≡C) -Au ( = 1-3) are compared with the corresponding Au-(C≡C) and Au-(C≡C) -H species.