title: Cationic cluster formation versus disproportionation of low-valent indium and gallium complexes of 2,2'-bipyridine.
abstract: Group 13 M(I) compounds often disproportionate into M(0) and M(III). Here, however, we show that the reaction of the M(I) salt of the weakly coordinating alkoxyaluminate [Ga(I)(C6H5F)2](+)[Al(OR(F))4](-) (R(F)=C(CF3)3) with 2,2'-bipyridine (bipy) yields the paramagnetic and distorted octahedral [Ga(bipy)3](2+)(•){[Al(OR(F))4](-)}2 complex salt. While the latter appears to be a Ga(II) compound, both, EPR and DFT investigations assign a ligand-centred [Ga(III){(bipy)3}(•)](2+) radical dication. Surprisingly, the application of the heavier homologue [(I)n(I)(C6H5F)2](+)[Al(OR(F))4](-) leads to aggregation and formation of the homonuclear cationic triangular and rhombic [In3(bipy)6](3+), [In3(bipy)5](3+) and [In4(bipy)6](4+) metal atom clusters. Typically, such clusters are formed under strongly reductive conditions. Analysing the unexpected redox-neutral cationic cluster formation, DFT studies suggest a stepwise formation of the clusters, possibly via their triplet state and further investigations attribute the overall driving force of the reactions to the strong In-In bonds and the high lattice enthalpies of the resultant ligand stabilized [M3](3+){[Al(OR(F))4](-)}3 and [M4](4+){[Al(OR(F))4](-)}4 salts.
authors.affiliation: Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Stefan-Meier Str. 21, 79104 Freiburg, Germany.
authors.forename: Martin R
authors.initials: MR
authors.lastname: Lichtenthaler
authors.affiliation: Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Stefan-Meier Str. 21, 79104 Freiburg, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Stahl
authors.affiliation: Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Stefan-Meier Str. 21, 79104 Freiburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Kratzert
authors.affiliation: Institut für Physikalische Chemie and Freiburg Institute of Advanced Studies (FRIAS), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Albertstr. 19, 79104 Freiburg, Germany.
authors.forename: Lorenz
authors.initials: L
authors.lastname: Heidinger
authors.affiliation: Institut für Physikalische Chemie and Freiburg Institute of Advanced Studies (FRIAS), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Albertstr. 19, 79104 Freiburg, Germany.
authors.forename: Erik
authors.initials: E
authors.lastname: Schleicher
authors.affiliation: Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Stefan-Meier Str. 21, 79104 Freiburg, Germany.
authors.forename: Julian
authors.initials: J
authors.lastname: Hamann
authors.affiliation: Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Stefan-Meier Str. 21, 79104 Freiburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Himmel
authors.affiliation: Institut für Physikalische Chemie and Freiburg Institute of Advanced Studies (FRIAS), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Albertstr. 19, 79104 Freiburg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Weber
authors.affiliation: Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstr. 21 and Stefan-Meier Str. 21, 79104 Freiburg, Germany.
authors.forename: Ingo
authors.initials: I
authors.lastname: Krossing