K2ReH9, eine Neubestimmung der Struktur

K₂ReH₉, a Redetermination of the Structure The crystal structure of K₂ReH₉ was redetermined on a single crystal via neutron diffraction (four circle diffractometer TAS2, 364 symmetrically independent reflections). The atomic arrangement determined by Abrahams et al. in 1964 could be confirmed in its essentials (Space group P62m, Z = 3). Nevertheless the structural parameters, which are much more precise now, yield positions of the hydrogen atoms showing that the co-ordination polyhedra of the two crystallographically independent [ReH₉^2–] – units are identical within the accuracy of the measurement. The results confirm the formula K₂ReH₉, an average structure with lower hydrogen content and statistically occupied hydrogen positions can be ruled out.