title: The gold(iii)-CO bond: a missing piece in the gold carbonyl complex landscape.
abstract: We investigate the Au(iii)-CO bond in the [(C∧N∧C)Au(iii)CO]+complex via charge-displacement (CD) analysis, revealing surprising peculiarities with respect to the Au(i)-CO bond. It shows a large Au(iii) ← CO σ donation and, unexpectedly, an even larger Au(iii) → CO π back-donation. The overall bonding picture, including a marked anisotropy in the Au(iii) → CO in-plane and out-of-plane π back-donation components, is consistent with a CO carbon atom highly susceptible to nucleophilic attack.
authors.affiliation: Dipartimento di Chimica, Biologia e Biotecnologie, Universita' degli Studi di Perugia, Via Elce di Sotto 8, I-06123, Perugia, Italy. paola.belanzoni@unipg.it.
authors.forename: Carlo Alberto
authors.initials: CA
authors.lastname: Gaggioli
authors.forename: Leonardo
authors.initials: L
authors.lastname: Belpassi
authors.forename: Francesco
authors.initials: F
authors.lastname: Tarantelli
authors.forename: Paola
authors.initials: P
authors.lastname: Belanzoni