title: A systematic investigation of coinage metal carbonyl complexes stabilized by fluorinated alkoxy aluminates.
abstract: The reaction of Cu(I), Ag(I), and Au(I) salts with carbon monoxide in the presence of weakly coordinating anions led to known and structurally unknown non-classical coinage metal carbonyl complexes [M(CO)n][A] (A = fluorinated alkoxy aluminates). The coinage metal carbonyl complexes [Cu(CO)n(CH2Cl2)m](+)[A](-) (n = 1, 3; m = 4-n), [Au2(CO)2Cl](+)[A](-), [(OC)nM(A)] (M = Cu: n = 2; Ag: n = 1, 2) as well as [(OC)3Cu⋅⋅⋅ClAl(OR(F))3] and [(OC)Au⋅⋅⋅ClAl(OR(F))3] were analyzed with X-ray diffraction and partially IR and Raman spectroscopy. In addition to these structures, crystallographic and spectroscopic evidence for the existence of the tetracarbonyl complex [Cu(CO)4](+)[Al(OR(F))4](-) (R(F) = C(CF3)3) is presented; its formation was analyzed with the help of theoretical investigations and Born-Fajans-Haber cycles. We discuss the limits of structure determinations by routine X-ray diffraction methods with respect to the C-O bond lengths and apply the experimental CO stretching frequencies for the prediction of bond lengths within the carbonyl ligand based on a correlation with calculated data. Moreover, we provide a simple explanation for the reported, partly confusing and scattered CO stretching frequencies of [Cu(I)(CO)n] units.
authors.affiliation: Institut für Anorganische und Analytische Chemie, Freiburger Materialforschungszentrum (FMF) and Freiburg Institute for Advanced Studies (FRIAS), Section Soft Matter Science, Universität Freiburg, Albertstrasse 19, 79104 Freiburg (Germany).
authors.forename: Julia
authors.initials: J
authors.lastname: Schaefer
authors.forename: Anne
authors.initials: A
authors.lastname: Kraft
authors.forename: Stefanie
authors.initials: S
authors.lastname: Reininger
authors.forename: Gustavo
authors.initials: G
authors.lastname: Santiso-Quinones
authors.forename: Daniel
authors.initials: D
authors.lastname: Himmel
authors.forename: Nils
authors.initials: N
authors.lastname: Trapp
authors.forename: Urs
authors.initials: U
authors.lastname: Gellrich
authors.forename: Bernhard
authors.initials: B
authors.lastname: Breit
authors.forename: Ingo
authors.initials: I
authors.lastname: Krossing
keywords: carbon monoxide; carbonyl ligands; coinage metals; density functional calculations; weakly coordinating anions