22 research outputs found
Analysis of Dislocation Mechanism for Melting of Elements: Pressure Dependence
In the framework of melting as a dislocation-mediated phase transition we
derive an equation for the pressure dependence of the melting temperatures of
the elements valid up to pressures of order their ambient bulk moduli. Melting
curves are calculated for Al, Mg, Ni, Pb, the iron group (Fe, Ru, Os), the
chromium group (Cr, Mo, W), the copper group (Cu, Ag, Au), noble gases (Ne, Ar,
Kr, Xe, Rn), and six actinides (Am, Cm, Np, Pa, Th, U). These calculated
melting curves are in good agreement with existing data. We also discuss the
apparent equivalence of our melting relation and the Lindemann criterion, and
the lack of the rigorous proof of their equivalence. We show that the would-be
mathematical equivalence of both formulas must manifest itself in a new
relation between the Gr\"{u}neisen constant, bulk and shear moduli, and the
pressure derivative of the shear modulus.Comment: 19 pages, LaTeX, 9 eps figure