The thermal expansion of a highly crystalline hexagonal BC2N compound synthesized under high temperature and pressure

The thermal expansion has been investigated for a highly crystalline hexagonal BC 2 N compound synthesized by the compression of a turbostratic B–C–N precursor with iron catalyst at the high temperature of 1500 °C and the high pressure of 5.5 GPa. The thermal expansion in the c direction is large and linear with an expansion coefficient of 35.86 × 10 −6 K −1 up to 1000 °C, while in the basal plane, the a dimension displays a slight linear contraction up to 750 °C with a contraction coefficient of −8.76 × 10 −7 K −1 , but above 750 °C a linear expansion is observed with a larger expansion coefficient of 1.52 × 10 −6 K −1 .