Experiments in liquid ammonia, originally aiming at reactions between Si containing Zintl clusters and transition metal complexes, lead to crystallization of several solvates of nineatomic cluster compounds.

The addition of Sn and Zn ions to [Ge ] clusters by reaction of [Ge ] with SnPh Cl , ZnCp* (Cp*=pentamethylcyclopentadienyl), or Zn [HC(Ph P=NPh) ] is reported. The resulting Sn- and Zn-bridged clusters [(Ge )M(Ge )] (M=Sn, q=4; M=Zn, q=6) display various coordination modes. The M atoms that coordinate to the open square of a C -symmetric [Ge ] cluster form strong covalent multicenter M-Ge bonds, in contrast to the M atoms coordinating to triangular cluster faces. Molecular orbital analyses show that the M atoms of the Ge M fragments coordinate to a second [Ge ] cluster with similar orbitals but in different ways. The [Ge Sn] unit donates two electrons to the triangular face of a second [Ge ] cluster with D symmetry, whereas [Ge Zn] acts as an electron acceptor when interacting with the triangular face of a D -symmetric [Ge ] unit.

The first example of a protonated and a rare example of a metal complex of the tetrahedral tetrel cluster anion [Ge4]4− was obtained from a solution of K6Rb6Ge17 in liquid ammonia in the presence of ZnPh2 and [18]crown-6.

The extraction of the silicide K 12 Si 17 with liquid ammonia in the presence of a sequestering agent and AuPPh 3 Cl or Zn(Cp*) 2 led to crystals of the solvate compound K 8 [Si 4 ][Si 9 ]·