Summary: Melting curve and Hugoniot of molybdenum up to
400 GPa by ab initio simulations
C. Cazorla1,2, M. J. Gillan1,2, S. Taioli3 and D. Alf`e1,2,3
London Centre for Nanotechnology, UCL, London WC1H OAH, U.K.
Department of Physics and Astronomy, UCL, London WC1E 6BT, U.K.
Department of Earth Sciences, UCL, London WC1E 6BT, U.K.
Abstract. We report ab initio calculations of the melting curve and Hugoniot of molybdenum
for the pressure range 0 - 400 GPa, using density functional theory (DFT) in the projector
augmented wave (PAW) implementation. We use the "reference coexistence" technique to
overcome uncertainties inherent in earlier DFT calculations of the melting curve of Mo. Our
calculated melting curve agrees well with experiment at ambient pressure and is consistent with
shock data at high pressure, but does not agree with the high pressure melting curve from
static compression experiments. Our calculated P(V ) and T(P) Hugoniot relations agree well
with shock measurements. We use calculations of phonon dispersion relations as a function of
pressure to eliminate some possible interpretations of the solid-solid phase transition observed
in shock experiments on Mo.