MgSrP3N5O2 - A Novel Oxonitridophosphate

MgSrP3N5O2 was synthesized at 6 GPa and 1000 degrees C starting from Mg3N2, Sr(N-3)(2), PON, and P3N5 utilizing the multianvil technique. By applying NH4Cl as mineralizer, single crystals were obtained. MgSrP3N5O2 exhibits a novel structure type [P2(1)/c (no. 14), a = 6.9404(8), b = 6.6103(7), c = 13.9317(12) angstrom, = 118.433(4)degrees, V = 562.06(10) angstrom(3), R-1 = 0.0289, wR(2) = 0.0468]. It is built up of a three-dimensional P(O, N)(4) tetrahedra network and exhibits an uncommon distribution of ring sizes. Besides 4- and 6-rings, the structure contains 10-rings as well. PXRD confirms phase purity. MAPLE calculations prove electrostatic plausibility of the crystal structure.