Melting-Temperature Measurements on alpha-Silicon Nitride to a Pressure of 37 GPa

The melting temperature of alpha-silicon nitride, up to a pressure of 37 GPa, was determined by using the diamond-anvil cell technique, together with laser heating and spectroradiometry. The melting temperature varied from 2200 ± 75 K at 3.5 GPa to 3600 ± 200 K at 37 GPa; the extrapolated temperature at 1 atm was estimated to be 2100 ± 75 K.