Because of its low chemical reactivity Si3N4 has hardly been used as a starting material for the preparation of multinary silicon nitrides or nitridosilicates, but has gained increasing importance as a nonoxidic material for high‐performance applications. A novel synthetic approach is presented, which starts from silicon diimide (Si(NH)2) and makes available a large variety of novel nitridosilicates. The structures of these nitridosilicates represent a significant extension from those found in the family of oxosilicates. Because of their outstanding chemical and physical stability, nitridosilicates might be of particular interest for the development of novel inorganic nitridic materials.

In all known oxoborates the linkage of BO(3) and BO(4) groups is performed via common corners. Here we present the high-pressure/high-temperature synthesis of Dy(4)B(6)O(15), which is the first oxoborate exhibiting edge-sharing BO(4) tetrahedra.

Innovative materials for phosphor converted white light-emitting diodes are in high demand owing to the huge potential of the light-emitting diode technology to reduce energy consumption worldwide. As the primary blue diode is already highly optimized, the conversion phosphors are of crucial importance for any further improvements. We report on the discovery of the high performance red phosphor Sr[Li 2 Al 2 O 2 N 2 ]:Eu 2+ meeting all requirements for a phosphor’s optical properties. It combines the optimal spectral position for a red phosphor, as defined in the 2016 Research & Development-plan of the United States government, with an exceptionally small spectral full width at half maximum and excellent thermal stability. A white mid-power phosphor-converted light-emitting diode prototype utilising Sr[Li 2 Al 2 O 2 N 2 ]:Eu 2+ shows an increase of 16% in luminous efficacy compared to currently available commercial high colour-rendering phosphor-converted light-emitting diodes, while retaining excellent high colour rendition. This phosphor enables a big leap in energy efficiency of white emitting phosphor-converted light-emitting-diodes.

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During the last 60 years, new high pressure techniques and their exploitation have permitted the extension of attainable pressure/volume conditions, increased versatility of the apparatus, and hydrostaticity of the attained pressure in a remarkable way. In preparative solid state chemistry, high-pressure/high-temperature synthesis always played a minor role due to technical difficulties and costs. Piston-cylinder and Belt-apparatus both were limited to the working range up to 3 and 10 GPa, respectively. New technical developments, which allow synthesis up to 25 GPa, open up an enormous field of sample synthesis in solid state chemistry. In the following, a short overview on the most important developments in multianvil-techniques is given with respect to their applications for solid state chemistry under high-pressure conditions.