MELTING PHENOMENA IN SOLIDIFIED GASES

Abstract

Based on the Lindemann melting criterion and the Gruneisen equation of state,  a  melting law log ( Tm/Tm° )=2 (r-1/3) log (v0/v) is derived, which for small com-  pressions gives a linear relation between  Tm and I av/vel as suggested recently by  Kraut and Kennedy. The correlation between  Tm  and lavivoi holds good very  satisfactorily for the high pressure data on the following solidified gases: He',  HO, Ne, A, Kr, Xe, I-1,, D„ N„ 0,, NH 3 , CO 2 ,  CH4, C2H4, C2H5  and C2H6.  The Gruneisen constant  r  calculated from the melting equation agrees well with  the values calculated independently from thermal measurements, where they are  available. In  He 4  and  H„  the decrease of 7 at high compressions along the  melting line is noticeable and agrees with the other thermal measurements.  The present equation relates melting phenomena in a quantitative way with general  solid state studies.