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Sn3P8N16 combines the structural versatility of nitridophosphates and Sn within one compound. It was synthesized as dark gray powder in a high‐pressure high‐temperature reaction at 800 °C and 6 GPa from Sn3N4 and P3N5. The crystal structure was elucidated from single‐crystal diffraction data (space group C2/m (no. 12), a=12.9664(4), b=10.7886(4), c=4.8238(2) Å, β=109.624(1)°) and shows a 3D‐network of PN4 tetrahedra, incorporating Sn in oxidation states +II and +IV. The Sn cations are located within eight‐membered rings of vertex‐sharing PN4 tetrahedra, stacked along the [001] direction. A combination of solid‐state nuclear magnetic resonance spectroscopy, 119Sn Mössbauer spectroscopy and density functional theory calculations was used to confirm the mixed oxidation of Sn. Temperature‐dependent powder X‐ray diffraction measurements reveal a low thermal expansion of 3.6 ppm/K up to 750 °C, beyond which Sn3P8N16 starts to decompose. [ABSTRACT FROM AUTHOR]

Sn3P8N16 combines the structural versatility of nitridophosphates and Sn within one compound. It was synthesized as dark gray powder in a high‐pressure high‐temperature reaction at 800 °C and 6 GPa from Sn3N4 and P3N5. The crystal structure was elucidated from single‐crystal diffraction data (space group C2/m (no. 12), a=12.9664(4), b=10.7886(4), c=4.8238(2) Å, β=109.624(1)°) and shows a 3D‐network of PN4 tetrahedra, incorporating Sn in oxidation states +II and +IV. The Sn cations are located within eight‐membered rings of vertex‐sharing PN4 tetrahedra, stacked along the [001] direction. A combination of solid‐state nuclear magnetic resonance spectroscopy, 119Sn Mössbauer spectroscopy and density functional theory calculations was used to confirm the mixed oxidation of Sn. Temperature‐dependent powder X‐ray diffraction measurements reveal a low thermal expansion of 3.6 ppm/K up to 750 °C, beyond which Sn3P8N16 starts to decompose. [ABSTRACT FROM AUTHOR]

The elements hydrogen, carbon, and nitrogen are among the most abundant in the solar system. Still, little is known about the ternary compounds these elements can form under the high‐pressure and high‐temperature conditions found in the outer planets' interiors. These materials are also of significant research interest since they are predicted to feature many desirable properties such as high thermal conductivity and hardness due to strong covalent bonding networks. In this study, the high‐pressure high‐temperature reaction behavior of malononitrile H2C(CN)2, dicyandiamide (H2N)2C=NCN, and melamine (C3N3)(NH2)3 was investigated in laser‐heated diamond anvil cells. Two previously unknown compounds, namely α‐C(NH)2 and β‐C(NH)2, have been synthesized and found to have fully sp3‐hybridized carbon atoms. α‐C(NH)2 crystallizes in a distorted β‐cristobalite structure, while β‐C(NH)2 is built from previously unknown imide‐bridged 2,4,6,8,9,10‐hexaazaadamantane units, which form two independent interpenetrating diamond‐like networks. Their stability domains and compressibility were studied, for which supporting density functional theory calculations were performed. [ABSTRACT FROM AUTHOR]

Layered silicates are a very versatile class of materials with high importance to humanity. The new nitridophosphates MP6N11 (M=Al, In), synthesized from MCl3, P3N5 and NH4N3 in a high‐pressure high‐temperature reaction at 1100 °C and 8 GPa, show a mica‐like layer setup and feature rare nitrogen coordination motifs. The crystal structure of AlP6N11 was elucidated from synchrotron single‐crystal diffraction data (space group Cm (no. 8), a=4.9354(10), b=8.1608(16), c=9.0401(18) Å, β=98.63(3)°), enabling Rietveld refinement of isotypic InP6N11. It is built up from layers of PN4 tetrahedra, PN5 trigonal bipyramids and MN6 octahedra. PN5 trigonal bipyramids have been reported only once and MN6 octahedra are sparsely found in the literature. AlP6N11 was further characterized by energy‐dispersive X‐ray (EDX), IR and NMR spectroscopy. Despite the vast amount of known layered silicates, there is no isostructural compound to MP6N11 as yet. [ABSTRACT FROM AUTHOR]

Owing to their widespread properties, nitridophosphates are of high interest in current research. Explorative high‐pressure high‐temperature investigations yielded various compounds with stoichiometry MP2N4 (M=Be, Ca, Sr, Ba, Mn, Cd), which are discussed as ultra‐hard or luminescent materials, when doped with Eu2+. Herein, we report the first germanium nitridophosphate, GeP2N4, synthesized from Ge3N4 and P3N5 at 6 GPa and 800 °C. The structure was determined by single‐crystal X‐ray diffraction and further characterized by energy‐dispersive X‐ray spectroscopy, density functional theory calculations, IR and NMR spectroscopy. The highly condensed network of PN4‐tetrahedra shows a strong structural divergence to other MP2N4 compounds, which is attributed to the stereochemical influence of the lone pair of Ge2+. Thus, the formal exchange of alkaline earth cations with Ge2+ may open access to various compounds with literature‐known stoichiometry, however, new structures and properties. [ABSTRACT FROM AUTHOR]

Recent advances in methods to access nitride systems by a high-pressure high-temperature approach have made possible the one-step synthesis of mixed ternary non-metal nitrides. As a prerequisite to use in a practical device, it is important to understand important bulk electronic properties, such as the band gap, as well as characterizing the presence and effect of defects that are present. In this work, the novel ternary nitride BP3N6 is studied using techniques sensitive to the partial electronic density of states, specifically X-ray absorption spectroscopy and X-ray emission spectroscopy. Complementary full-potential all-electron density functional theory (DFT) calculations allow important bulk electronic parameters, such as the band gap, to be elucidated. The band gap of BP3N6 has been determined to be 3.9 ± 0.2 eV and 4.1 ± 0.4 eV at the B K- and N K-edges, respectively. This is close to a theoretical value of 4.3 eV predicted by the PBEsol exchange–correlation functional and considerably less than a value of 5.8 eV predicted by the modified Becke–Johnson exchange–correlation functional. X-Ray excited optical luminescence (XEOL) measurements are performed to interrogate the presence of point defects in this system. Together with DFT calculations, these measurements reveal the presence of nitrogen vacancies which lead to multiple mid-gap trap states. [ABSTRACT FROM AUTHOR]

Sn 3 P 8 N 16 combines the structural versatility of nitridophosphates and Sn within one compound. It was synthesized as dark gray powder in a high-pressure high-temperature reaction at 800 °C and 6 GPa from Sn 3 N 4 and P 3 N 5 . The crystal structure was elucidated from single-crystal diffraction data (space group C2/m (no. 12), a=12.9664(4), b=10.7886(4), c=4.8238(2) Å, β=109.624(1)°) and shows a 3D-network of PN 4 tetrahedra, incorporating Sn in oxidation states +II and +IV. The Sn cations are located within eight-membered rings of vertex-sharing PN 4 tetrahedra, stacked along the [001] direction. A combination of solid-state nuclear magnetic resonance spectroscopy, 119 Sn Mössbauer spectroscopy and density functional theory calculations was used to confirm the mixed oxidation of Sn. Temperature-dependent powder X-ray diffraction measurements reveal a low thermal expansion of 3.6 ppm/K up to 750 °C, beyond which Sn 3 P 8 N 16 starts to decompose., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Nitridophosphates and nitridogermanates attract high interest in current research due to their structural versatility. Herein, the elastic properties of GeP 2 N 4 were investigated by single-crystal X-ray diffraction (XRD) upon compression to 44.4(1) GPa in a diamond anvil cell. Its isothermal bulk modulus was determined to be 82(6) GPa. At 44.4(1) GPa, laser heating resulted in the formation of multiple crystalline phases, one of which was identified as unprecedented germanium nitridophosphate GePN 3 . Its structure was elucidated from single-crystal XRD data ( C 2/ c (no. 15), a = 8.666(5), b = 8.076(4), c = 4.691(2) Å, β = 101.00(7)°) and is built up from layers of GeN 6 octahedra and PN 4 tetrahedra. The GeN 6 octahedra form double zigzag chains, while the PN 4 tetrahedra are found in single zigzag chains. GePN 3 can be recovered to ambient conditions with a unit cell volume increase of about 12%. It combines P V and Ge IV in a condensed nitridic network for the first time.

The elements hydrogen, carbon, and nitrogen are among the most abundant in the solar system. Still, little is known about the ternary compounds these elements can form under the high-pressure and high-temperature conditions found in the outer planets' interiors. These materials are also of significant research interest since they are predicted to feature many desirable properties such as high thermal conductivity and hardness due to strong covalent bonding networks. In this study, the high-pressure high-temperature reaction behavior of malononitrile H 2 C(CN) 2 , dicyandiamide (H 2 N) 2 C=NCN, and melamine (C 3 N 3 )(NH 2 ) 3 was investigated in laser-heated diamond anvil cells. Two previously unknown compounds, namely α-C(NH) 2 and β-C(NH) 2 , have been synthesized and found to have fully sp 3 -hybridized carbon atoms. α-C(NH) 2 crystallizes in a distorted β-cristobalite structure, while β-C(NH) 2 is built from previously unknown imide-bridged 2,4,6,8,9,10-hexaazaadamantane units, which form two independent interpenetrating diamond-like networks. Their stability domains and compressibility were studied, for which supporting density functional theory calculations were performed., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Layered silicates are a very versatile class of materials with high importance to humanity. The new nitridophosphates MP 6 N 11 (M=Al, In), synthesized from MCl 3 , P 3 N 5 and NH 4 N 3 in a high-pressure high-temperature reaction at 1100 °C and 8 GPa, show a mica-like layer setup and feature rare nitrogen coordination motifs. The crystal structure of AlP 6 N 11 was elucidated from synchrotron single-crystal diffraction data (space group Cm (no. 8), a=4.9354(10), b=8.1608(16), c=9.0401(18) Å, β=98.63(3)°), enabling Rietveld refinement of isotypic InP 6 N 11 . It is built up from layers of PN 4 tetrahedra, PN 5 trigonal bipyramids and MN 6 octahedra. PN 5 trigonal bipyramids have been reported only once and MN 6 octahedra are sparsely found in the literature. AlP 6 N 11 was further characterized by energy-dispersive X-ray (EDX), IR and NMR spectroscopy. Despite the vast amount of known layered silicates, there is no isostructural compound to MP 6 N 11 as yet., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Owing to their widespread properties, nitridophosphates are of high interest in current research. Explorative high-pressure high-temperature investigations yielded various compounds with stoichiometry MP 2 N 4 (M=Be, Ca, Sr, Ba, Mn, Cd), which are discussed as ultra-hard or luminescent materials, when doped with Eu 2+ . Herein, we report the first germanium nitridophosphate, GeP 2 N 4 , synthesized from Ge 3 N 4 and P 3 N 5 at 6 GPa and 800 °C. The structure was determined by single-crystal X-ray diffraction and further characterized by energy-dispersive X-ray spectroscopy, density functional theory calculations, IR and NMR spectroscopy. The highly condensed network of PN 4 -tetrahedra shows a strong structural divergence to other MP 2 N 4 compounds, which is attributed to the stereochemical influence of the lone pair of Ge 2+ . Thus, the formal exchange of alkaline earth cations with Ge 2+ may open access to various compounds with literature-known stoichiometry, however, new structures and properties., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)