Radical-Induced Hydrosilylation Reactions for the Functionalization of Two-Dimensional Hydride Terminated Silicon Nanosheets.

Herein we present the functionalization of freestanding silicon nanosheets (SiNSs) by radical-induced hydrosilylation reactions. An efficient hydrosilylation of Si-H terminated SiNSs can be achieved by thermal initiation or the addition of diazonium salts with a variety of alkene or alkyne derivatives. The radical-induced hydrosilylation is applicable for a wide variety of substrates with different functionalities, improving the stability and dispersibility of the functional SiNSs in organic solvents and potentially opening up new fields of application for these hybrid materials.

[Ge2](4-) Dumbbells with Very Short Ge-Ge Distances in the Zintl Phase Li3NaGe2: A Solid-State Equivalent to Molecular O2.

The novel ternary Zintl phase Li3NaGe2 comprises alkali-metal cations and [Ge2](4-) dumbbells. The diatomic [Ge2](4-) unit is characterized by the shortest Ge-Ge distance (2.390(1) Å) ever observed in a Zintl phase and thus represents the first Ge=Ge double bond under such conditions, as also suggested by the (8-N) rule.

Li18Na2Ge17--a compound demonstrating cation effects on cluster shapes and crystal packing in ternary Zintl phases.

The novel ternary Zintl phase Li18Na2Ge17 was synthesized from a stoichiometric melt and characterized crystallographically. It crystallizes in the trigonal space group P31m (No. 157) with a = 17.

Implications of the crystal structure of the ammonia solvate [Au(NH3)2]Cl·4NH3.

Crystals of diammine gold(I) chloride ammonia (1/4), [Au(NH(3))(2)]Cl·4NH(3), have been grown from solutions of AuCl in liquid ammonia. The X-ray diffraction analysis (at 123 K) has shown that the crystals feature an extensive network of hydrogen bonds between the [H(3)N-Au-NH(3)](+) cations (with C(i) symmetry) and the Cl(-) anions, including also the ammonia molecules. There is no evidence for an emerging increase of the coordination number of the gold atom by adopting another ammonia molecule or by approaching a chloride anion.