Abstract: | CsNb3Br7S: Synthesis, Structure, and Bonding States The reaction of NbBr5 with Nb, Cs and S in a sealed Nb container affords CsNb3Br7S at 800°C (3 days). Further on isotypic compounds of the general formula ANb3X7Ch with A = Rb, Cs; X = Cl, Br and Ch = S, Se are obtained. CsNb3Br7S crystallizes monoclinic (space group P21/a, Z = 2), with the lattice parameters a = 707.4(2), b = 1 888.4(4), c = 994.1(2) pm and β = 98.59(2)°. The crystal structure contains Nb3 clusters being linked by two additional Nb? Nb bonds to form infinite chains. Adjacent chains are bridged by Cs atoms in a cubeoctahedral coordination sphere of Br atoms. Similar with Nb3Br8 seven electrons occupy metal—metal bonding states. |