CRYSTALLINE PHOSPHORUS(V) NITRIDE IMIDE, HPN2 AND DPN2, RESPECTIVELY,- STRUCTURE DETERMINATION WITH X-RAY, SYNCHROTRON, AND NEUTRON RADIATION

Microcrystalline HPN2 resp. DPN2 was obtained by the reaction of P3N5 With NH3 resp. ND3 in high-pressure autoclaves under ammonothermal con ditions (T = 550 degrees C, p(NH3 resp. ND3) = 6 kbar) within 14 d. Th e structure was solved on DPN2 by synchrotron and neutron diffraction data including the D-positions. DPN2: P2(1)2(1)2(1) (Nr. 19), a = 4.65 50(2) Angstrom; b = 4.6591(2) Angstrom; c = 7.0560(3) Angstrom, Z = 4, Neutron diffraction time-of-flight: R-Bragg(F-o(2)) = 0.0184, 33 refl ections (d = 1.626 Angstrom - d = 5.278 Angstrom) R-Bragg(F-o(2)) = 0. 0218, 93 reflections (d = 1.080 Angstrom - d = 2.623 Angstrom) DPN2 co ntains corner-sharing tetrahedra PN4/2. These form a three-dimensional network as it is observed undistorted in 'idealized' beta-cristobalit e. The deuterons are bonded to one half of the nitrogen atoms in an or dered way.