PRESSURE DEPENDENCES OF THE MELTING TEMPERATURE OF GRAPHITE AND THE ELECTRICAL-RESISTIVITY OF LIQUID CARBON

The melting line of graphite and the electrical resistivity of liquid carbon are investigated along the melting line by a flash-heating expe riment under high pressures. The melting temperature of graphite incre ased from 4650 K at 1.4 GPa to a maximum of 4790 K at 5.6 GPa, then de creased to 4640 K at 9.4 GPa, The electrical resistivity of liquid car bon along the melting line decreased from 900 to 600 mu Omega cm with an increase of pressure of 1.4 to 9.4 Gpa. Changes in slopes of the me lting line and of the electrical resistivity at about 5.6 GPa suggest a possibility for a first-order phase transition in liquid carbon.