Pressure-induced Pb-Pb bonding and phase transition in PbSnO.

High-pressure single-crystal to 20 GPa and powder diffraction measurements to 50 GPa, show that the structure of PbSnO strongly distorts on compression with an elongation of one axis. A structural phase transition occurs between 10 GPa and 12 GPa, with a change of space group from Pbam to Pnam. The resistivity decreases by more than six orders of magnitude when pressure is increased from ambient conditions to 50 GPa.