Synthese und Struktur von Na2PtH4, einem ternären Hydrid mit quadratisch planaren PtH42−-Baugruppen

Synthesis and Structure of Na₂PtH₄, a Ternary Hydride with Square Planar PtH₄^2? Groups The red violet hydride Na₂PtH₄ is synthesized by the reaction of sodium hydride with platinum in a hydrogen atmosphere at a temperature between 280°C and 310°C. The crystal structure was determined by X-ray and neutron diffraction experiments (Na₂PtD₄) on powdered samples. Na₂PtH₄ crystallizes in a new structure type (a = 5.274(2), c = 6.788(3) Å; space group I4/mmm; Z = 2), which is characterized by planar, diamagnetic PtH₄^2? anions. Structural relations and relative stabilities of the Na₂PtH₄ and the K₂PtCl₄ structure type are to be discussed.     

Synthese und Struktur von AlTaO4

Synthesis and Structure of AlTaO₄ Single crystals of AlTaO₄ were prepared between 1310–1360°C and investigated by X-ray single crystal methods. It crystallizes with tetragonal symmetry (a = 460.6₅; c = 298.5 pm; space group D–P4₂/mnm). AlTaO₄ has got a statistical metal distribution with rutil structure. It shows metastable character in respect to lower temperatures.