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 conditions (T = 550 degrees C, p(NH3 resp. ND3) = 6 kbar) within 14 d. The 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 = 4.6550(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 reflections (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 contains corner-sharing tetrahedra PN4/2. These form a three-dimensional network as it is observed undistorted in 'idealized' beta-cristobalite. The deuterons are bonded to one half of the nitrogen atoms in an ordered way.