Multianvil-Synthese, Pulver-Röntgenstrukturanalyse, 31P-MAS-NMR- und FTIR-Spektroskopie sowie Materialeigenschaften von γ-P3N5, einer Hochdruckphase von binärem Phosphor(V)-nitrid mit verzerrt quadratischen PN5-Pyramiden und PN4-TetraedernProfessor Welf Bronger zum 70. Geburtstag gewidmet

Abstract

Professor Welf Bronger zum 70. Geburtstag gewidmetInhaltsübersicht. Die Hochdruckphase γ-P 3 N 5 wurde ausgehend von teilkristallinem P 3 N 5 bei einem Druck von 11 GPa und einer Temperatur von 1500°C in einer Multianvil-Apparatur synthetisiert. Die Kristallstruktur wurde auf der Basis von Pulver-Röntgenbeugungsdaten mit Direkten Methoden gelöst und nach dem Rietveld-Verfahren verfeinert (Imm2, a ϭ 1287,21(4), b ϭ 261,312 (6), c ϭ 440,03(2) pm, Z ϭ 2, R p ϭ 0,073, wR p ϭ 0,094, R F ϭ 0,048). γ-Phosphor(V)-nitrid kristallisiert demnach in einer Raumnetzstruktur aus eckenverknüpften PN 4 -Tetraedern und verzerrt qua-Abstract. The high-pressure phase γ-P 3 N 5 was synthesized at a pressure of 11 GPa and a temperature of 1500°C in a multianvil apparatus. Partially crystalline P 3 N 5 has been used as a starting material. The crystal structure was solved by direct methods on the basis of X-ray powder diffraction data and it was refined by the Rietveld method (Imm2, a ϭ 1287.21(4), b ϭ 261.312(6), c ϭ 440.03(2) pm, Z ϭ 2, R p ϭ 0.073, wR p ϭ 0.094, R F ϭ 0.048). γphosphorus nitride crystallizes in a three-dimensional network structure built up from corner sharing PN 4 tetrahedra and transedge sharing distorted PN 5 square pyramids. In the 31 P-MAS-NMR spectrum two sharp isotropic resonances with an intensity

Phenakite‐Type BeP2N4—A Possible Precursor for a New Hard Spinel‐Type Material

“…So far in nitridophosphates only coordination numbers of phosphorus up to five have been experimentally realized (cf. γ‐P 3 N 5 )8, 9 and a sixfold coordination for P has been predicted for hypothetic δ‐P 3 N 5 10…”

“…The calculated bond lengths for PN and BeN in spinel‐type BeP 2 N 4 and inverse spinel‐type BeP 2 N 4 are listed in Table 5. They are all in the range found in Be 3 N 2 and P 3 N 5 compounds 7–9. 29 Be [6] N distances are longer than Be [4] N distances, as are the bond lengths of P [6] N in comparison to the bond lengths of P [4] N.…”

“…A significant increase in density and mechanical hardness is achieved upon transformation into the high‐pressure polymorph γ‐P 3 N 5 8. 9 In accordance to the pressure‐coordination rule, a partial increase of the coordination number of phosphorus from 4 to 5 occurs, thus leading to a coordination according to P [4] P 2 [5] N [2] N 4 [3] . At higher pressures (about 40 GPa) theoretical studies suggest a transformation into hypothetic δ‐P 3 N 5 with a kyanite‐type structure comprising PN 6 octahedra and PN 4 tetrahedra 10.…”

High‐Pressure Synthesis of Tantalum Nitride Having Orthorhombic U2S3 Structure

“…spinel structure (g-M 3 N 4 , where M ¼ Si, Ge), [12] orthorhombic g-P 3 N 5 , [13] nitrides of the group 4 elements having cubic Th 3 P 4 structure (c-A 3 N 4 , where A ¼ Zr, Hf), [14] and four noble metal nitrides. [15] The interest in new high-pressure nitrides is only partially governed by the intention to find materials with enhanced elastic moduli and hardness.…”

CdP2N4 and MnP2N4 – Ternary Transition‐Metal Nitridophosphates

“…[1] Binary P 3 N 5 , which was first described in 1862, although its structure was only elucidated in 1997, [2][3][4] finds application as a gate insulator material in electronic devices and has been used for the production of incandescent lamps. [12][13][14][15] Recent work shows that Eu 2+ -doped nitridophosphates like MP 2 N 4 :Eu 2+ (M = Ca, Sr, Ba) and Ba 3 P 5 N 10 X:Eu 2+ (X = Cl, I, Br) are promising luminescent materials that may find application as phosphors in (pc)LEDs. [12][13][14][15] Recent work shows that Eu 2+ -doped nitridophosphates like MP 2 N 4 :Eu 2+ (M = Ca, Sr, Ba) and Ba 3 P 5 N 10 X:Eu 2+ (X = Cl, I, Br) are promising luminescent materials that may find application as phosphors in (pc)LEDs.…”