Polymeric carbon nitride materials have been used in numerous light‐to‐energy conversion applications ranging from photocatalysis to optoelectronics. For a new application and modelling, we first refined the crystal structure of potassium poly(heptazine imide) (K‐PHI)—a benchmark carbon nitride material in photocatalysis—by means of X‐ray powder diffraction and transmission electron microscopy. Using the crystal structure of K‐PHI, periodic DFT calculations were performed to calculate the density‐of‐states (DOS) and localize intra band states (IBS). IBS were found to be responsible for the enhanced K‐PHI absorption in the near IR region, to serve as electron traps, and to be useful in energy transfer reactions. Once excited with visible light, carbon nitrides, in addition to the direct recombination, can also undergo singlet–triplet intersystem crossing. We utilized the K‐PHI centered triplet excited states to trigger a cascade of energy transfer reactions and, in turn, to sensitize, for example, singlet oxygen (1O2) as a starting point to synthesis up to 25 different N‐rich heterocycles.

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Polymere Kohlenstoffnitridmaterialien wurden erfolgreich in zahlreichen Anwendungen zur Umwandlung von Licht in Energie, die von der Photokatalyse bis zur Optoelektronik reichen, eingesetzt. Für eine neue Anwendung und Modellierung verfeinerten wir zunächst die Kristallstruktur von Kalium‐Polyheptazinimid (K‐PHI) – einem Referenz‐Kohlenstoffnitridmaterial in der Photokatalyse – mithilfe von Röntgenpulverdiffraktometrie und Transmissionselektronenmikroskopie. Unter Verwendung der Kristallstruktur von K‐PHI wurden periodische DFT‐Berechnungen durchgeführt, um die Zustandsdichte zu berechnen und Intra‐Banden‐Zustände (IBS) zu lokalisieren. Es wurde festgestellt, dass IBS für die erhöhte Absorption von K‐PHI im nahen IR‐Bereich verantwortlich sind, als Elektronenfallen dienen und bei Energietransferreaktionen nützlich sind. Einmal mit sichtbarem Licht angeregt, können Kohlenstoffnitride neben der direkten Rekombination auch Intersystem Crossing vom Singulett‐ in den Triplett‐Zustand durchlaufen. Wir nutzen die angeregten zentrierten Triplett‐Zustände im K‐PHI, um eine Kaskade von Energieübertragungsreaktionen auszulösen und im Gegenzug z. B. Singulett‐Sauerstoff (1O2), als Ausgangspunkt für die Synthese von bis zu 25 verschiedenen N‐reichen Heterozyklen, zu sensibilisieren.

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The new title perovskite is synthesized from mixtures of Ca(VO3)2, Co(VO3)2, and Co (14-18 GPa, 900-1300°C, 0.5-8 h). The product is characterized by powder and single crystal XRD, SEM, magnetic susceptibility, and electrical resistivity measurements. CaCo3V4O12 crystallizes in the cubic space group Im3 with Z = 2 and is the first double perovskite with Co 2+ ions at the A' sites. The compound orders antiferromagnetically around 100 K and exhibits semimetallic conductivity in the temperature range 1.6-370 K. -(OVSYANNIKOV*, S. V.; ZAINULIN, Y. G.; KADYROVA, N. I.; TYUTYUNNIK, A. P.; SEMENOVA, A. S.; KASINATHAN, D.; TSIRLIN, A. A.; MIYAJIMA, N.; KARKIN, A. E.; Inorg. Chem. 52 (2013) 20, 11703-11710, http://dx.doi.org/10.1021/ic400649h ; Inst. Solid State Chem., Ural Branch Russ.

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Thermal decomposition of (NH4)2[OsxPt1-xCl6] as single-source precursors for Os-Pt binary alloys has been investigated under ambient and high pressure up to 40 GPa. Thermal decomposition of mixed-metal (NH4)2[OsxPt1-xCl6] precursor in hydrogen atmosphere (reductive environment) under ambient pressure results in formation of β-trans-[Pt(NH3)2Cl2] and α-trans-[Pt(NH3)2Cl2] crystalline intermediates as well as single and twophase Os-Pt binary alloys. For the first time, direct thermal decomposition of coordination compound under pressure has been investigated. A formation of pure metallic alloys from single-source precursors under pressure has been shown. Miscibility between fccand hcpstructured alloys has been probed up to 50 GPa by in situ high-pressure X-ray diffraction. Miscibility gap between fccand hcp-structured alloys does not change its positions with pressure up to at least 50 GPa.