Solid-State Chemistry with Nonmetal Nitrides

Among the nonmetal nitrides, the polymeric binary compounds BN and Si3N4are of particular interest for the development of materials for high-performance applications. The outstanding features of both substances are their thermal, mechanical, and chemical stability, coupled with their low density. Because of their extremely low reactivity, boron and silicon nitride are hardly ever used as starting materials for the preparation of ternary nitrides, but are used primarily in the manufacture of crucibles or other vessels or as insulation materials. The chemistry of ternary and higher nonmetal nitrides that contain electropositive elements and are thus analogous with the oxo compounds such as borates, silicates, phosphates, or sulfates was neglected for many years. Starting from the recent successful preparation of pure P3N5, a further binary nonmetal nitride which shows similarities with Si3N4 with regard to both its structure and properties, this review deals systematically with the solid-state chemistry of ternary and higher phosphorus(V) nitrides and the relationship between the various types of structure found in this class of substance and the resulting properties and possible applications. From the point of view of preparative solid-state chemistry the syntheses, structures, and properties of the binary nonmetal nitrides BN, Si3N4, and P3N5 will be compared and contrasted. The chemistry of the phosphorus(V) nitrides leads us to expect that other nonmetals such as boron, silicon, sulfur, and carbon will also participate in a rich nitride chemistry, as initial reports indeed indicate

Zur Kenntnis von Lithium-phosphor(V)-nitrid. Reindarstellung und Verfeinerung der Kristallstruktur von LiPN2

Reines Lithium-phosphor(V)-nitrid (LiPN2 ) wurde durch Festkörperreaktion der binären Nitride L i 3N und P3N5 erhalten. Die Kristallstruktur von LiPN2 wurde auf der Basis von Röntgen-Pulverdiffraktometerdaten mit Hilfe der Rietveld-Methode verfeinert (I42d; a = 457,5(2) pm; c = 711,8(3) pm; 31 beob. Reflexe 20° < 2Θ <105°; Germanium-Monochromator, CuK^; R(wp) = 0,059; R(I, hkl) = 0,061). Die Kristallstruktur von LiPN2 leitet sich vom Chalcopyrit- Typ ab. Phosphor und Stickstoff bilden ein dreidimensionales Netz eckenverknüpfter PN4 - Tetraeder (Ρ—Ν 164,5(7) pm; P-N—Ρ 123,6(8)°). Die Lithium-Kationen besetzen die verbleibenden Lücken. Sie sind verzerrt tetraedrisch von jeweils vier Stickstoff-Atomen koordiniert (Li—Ν 209,3(10) pm)

Trisodium Trimetaphosphimate Monohydrate

The trimetaphosphimate anion (PO2NH)33- in trisodium cyclo-tri--imidotriphosphate monohydrate, Na3(PO2NH)3.H2O, exhibits a chair conformation. Two trimetaphosphimate rings are linked to each other by six N-HO hydrogen bonds forming pairs. These units are interconnected by O-HO hydrogen bonds through water molecules forming columns

Rubidium metaborate, Rb3B3O6

Rubidium metaborate, Rb3B3O6, was obtained by the reaction of Rb2CO3 and BN using a radiofrequency furnace at a maximum reaction temperature of 1173 K. The crystal structure has been determined by single-crystal X-ray diffraction. The space group is , with all atoms positioned on a twofold axis (Wyckoff site 18e). The ionic compound is isotypic with Na3B3O6, K3B3O6 and Cs3B3O6

Eu2Si5N8 and EuYbSi4N7

The crystal structures of dieuropium penta siliconoctanitride, Eu2Si5N8, and europium ytterbium tetrasiliconheptanitride, EuYbSi4N7, are based on three-dimensional networks of corner-sharing SiN4 tetrahedra. Eu2Si5N8 is isotypic with the previously reported Sr and Ba analogues; EuYbSi4N7 is isotypic with SrYbSi4N7 and BaYbSi4N7

Tetraammonium Tetrametaphosphimate Tetrahydrate

The tetrametaphosphimate ring in the title compound, (NH4)4+(PO2NH)4-.4H2O exhibits a chair conformation. The tetrametaphosphimate rings are linked by N-HO bonds forming columns along [100]. These columns are interconnected by O-HO and N-HO hydrogen bonds through water molecules and ammonium ions. All H atoms are involved in hydrogen bonding

Synthese, Kristallstruktur und Eigenschaften von Tetraaminophosphonium-iodid P(NH2)4I

Abstract The title compound has been prepared starting from phosphorothionic triamide SP(NH2)3 by methylation of the sulfur atom and subsequent ammonolysis reaction in dry acetonitrile and dichloromethane, respectively, both at room temperature. Suitable single crystals are obtained from an acetonitrile solution in a temperature gradient between 70 °C and room temperature. The crystal structure of [P(NH2)4]I has been determined by single crystal X-ray methods (P4/nbm; a = 842.6(2), c = 486.7(2) pm, Z = 2). In the solid [P(NH2)4]+ - and I−-ions are found with significant N - H···I-hydrogen bonding interactions between anions and cations (H -I: 276.4 pm). The P - N - bond length in the cation (160.7(2) pm) represents the shortest P - NH2 bond distance reported to date indicating a significant electrostatic strengthening. The condensation behaviour of [P(NH2)4]I in solution and in the solid has been investigated.</jats:p