The Reduced Nitridogermanates(III) Ca(6) [Ge(2) N(6) ] and Sr(6) [Ge(2) N(6) ] with Ge-Ge Bonds

The first nitridogermanates(III) Ca(6) [Ge(2) N(6) ] and Sr(6) [Ge(2) N(6) ] were synthesized from sodium flux and structurally characterized by powder and single crystal X-ray diffraction, respectively. They crystallize isostructurally to each other and homeotypic to Ca(6) [Cr(2) N(6) ]H in space group R 3‾ . They feature unprecedented, mutually isolated, ethane-like [Ge(III) (2) N(6) ](12-) anions in a staggered conformation. The compounds are semiconductors according to resistivity measurements and electronic structure calculations, yielding band gaps of 1.1 eV for Ca(6) [Ge(2) N(6) ] and 0.2 eV for Sr(6) [Ge(2) N(6) ].