Melting of B12P2 boron subphosphide under pressure
  Melting of boron subphosphide (B12P2) to 26 GPa has been studied by in situ synchrotron X-ray powder diffraction in a laser-heated diamond anvil cell, and by quenching and electrical resistance measurements in a toroid-type high-pressure apparatus. B12P2 melts congruently, and the melting curve has a positive slope of 23(6) K/GPa. No solid-state phase transition was observed up to the melting in the whole pressure range under study. 
Vladimir L. Solozhenko, Vladimir A. Mukhanov, Petr S. Sokolov, Yann Le   Godec, Kirill A. Cherednichenko, Zuzana Kon\^opkov\'a
cond-mat.mtrl-sci