title: Structure and spectroscopic properties of the dimeric copper(I) N-heterocyclic carbene complex [Cu₂(CNC(t-Bu))₂](PF₆)₂.
abstract: In recent years, the use of copper N-heterocyclic carbene (NHC) complexes has expanded to fields besides catalysis, namely medicinal chemistry and luminescence applications. In the latter case, multinuclear copper NHC compounds have attracted interest, however, the number of these complexes in the literature is still quite limited. Bis[μ-1,3-bis(3-tert-butylimidazolin-2-yliden-1-yl)pyridine]-1κ(4)C(2),N:N,C(2');2κ(4)C(2),N:N,C(2')-dicopper(I) bis(hexafluoridophosphate), [Cu2(C19H25N5)2](PF6)2, is a dimeric copper(I) complex bridged by two CNC, i.e. bis(N-heterocyclic carbene)pyridine, ligands. Each Cu(I) atom is almost linearly coordinated by two NHC ligands and interactions are observed between the pyridine N atoms and the metal centres, while no cuprophilic interactions were observed. Very strong absorption bands are evident in the UV-Vis spectrum at 236 and 274 nm, and an emission band is observed at 450 nm. The reported complex is a new example of a multinuclear copper NHC complex and a member of a compound class which has only rarely been reported.
authors.affiliation: Chair of Inorganic Chemistry/Molecular Catalysis, Catalysis Research Center & Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer-Strasse 1, 85747 Garching bei München, Germany.
authors.forename: Korbinian
authors.initials: K
authors.lastname: Riener
authors.affiliation: Chair of Inorganic Chemistry/Molecular Catalysis, Catalysis Research Center & Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer-Strasse 1, 85747 Garching bei München, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Pöthig
authors.affiliation: Chair of Inorganic Chemistry/Molecular Catalysis, Catalysis Research Center & Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer-Strasse 1, 85747 Garching bei München, Germany.
authors.forename: Mirza
authors.initials: M
authors.lastname: Cokoja
authors.affiliation: Chair of Inorganic Chemistry/Molecular Catalysis, Catalysis Research Center & Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer-Strasse 1, 85747 Garching bei München, Germany.
authors.forename: Wolfgang A
authors.initials: WA
authors.lastname: Herrmann
authors.affiliation: Chair of Inorganic Chemistry/Molecular Catalysis, Catalysis Research Center & Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer-Strasse 1, 85747 Garching bei München, Germany.
authors.forename: Fritz E
authors.initials: FE
authors.lastname: Kühn
keywords: catalysis; crystal structure; dimeric copper(I) N-heterocyclic carbene complex; spectroscopic properties