A Novel Framework Antimony (III) Phosphate: Synthesis and Structure of NaSb3O2(PO4)2

The antimony (III) phosphate, NaSb3O2(PO4)2, is a framework structure built from SbIII and PV centers; orthorhombic, space group Pca21 (No. 29), a=13.944(3), b=6.6822(13), c=20.886(4) ?, V=1946.1(7) ?3, Z=8. Stereochemically active lone pairs of electrons associated with SbIIIO5 and SbIIIO4 polyhedra point into eight-ring channels, approximately 5×7 ?2, which dominate the architecture of the title compound. Charge-compensating sodium cations occupy the remaining space in the channels.