New P2 Compound with Brucite-Like Layers: Potassium Lithiostannate

A new compound with brucite-like layers, K0.72Li0.24Sn0.76O2, has been obtained
two ways,
via solid-state reactions: with a big excess of KOH and in a controllable
atmosphere without water and carbon dioxide. It has P2 structure (in
Hagenmuller’s definition) as previously described for K0.70Zn0.35Sn0.65O2. The latter
compound has been repeatedly prepared using the new technique presented
here. The structure was refined using powder X-ray profile analysis.
Lithium cations are disordered with tin (+4) in the rigid part and
introduce “acid” properties. Both types of potassium
positions are split. The metastable P3 phase also appears in the K2O–Li2O–SnO2 system. The
sodium analogue Na0.72Li0.24Sn0.76O2 with P2 structure has been prepared using an ion-exchange
technique.