The Melting Laws at High PressuresBY 0. P. SHARMA (a), G. S. SHARMA (a), and S. PRAKASH (b) Presently, a number of equations are available showing the pressure dependence of the melting temperature in solids due to the thermal effect. Simon's empirical fusion equation [l, 21 to fit the experimentally measured values of melting temperature at elevated pressure is one of the important and extensively used relations which is given by A2 T, = T, , (1 + $) ,where T, , and T, are the melting temperatures at zero excess pressure and at excess pressure P, respectively. A , and A , are constants known as Simon's constants. However, this equation cannot be used satisfactorily for extrapolating high pressure laboratory melting data [3]. Also, there is no theory [4,5] so far which could give the values of A , matching well with the experimentally found values, and there is no identification of Al and A, with some physical properties of the solid. Kraut and Kennedy [6,7] also gave an empirical relationship between the room temperature compression AVjV, and the melting temperature to explain experimental measurements of T, , Recently, Kumari and Dass [8,9] have also made a similar attempt and suggested a relationship in the form