Novel Ultrahard Materials

Superhard materials are needed to replace diamond in applications at high temperatures, where diamond is unstable. Novel carbon‐ and boron‐based materials are described whose discovery or postulation has greatly stimulated research in this area. The use of calculations to predict the properties of new materials is illustrated for B‐C 3 N 4 , which was synthesized only after its structure (see Figure) had been calculated. magnified image