Phase Diagram of Rubidium to 150 000 kg/cm2and 400°C

Abstract

A room temperature transition was found in rubidium at 107 000 kg/${\mathrm{cm}}^2$. It is characterized by an abrupt increase in electrical resistance of about 12 to 15%. The melting temperature increased with pressure in a normal manner up to about 25 000 kg/${\mathrm{cm}}^2$; then the rate of rise diminished rapidly until a maximum melting point of about 280°C was reached at 50 000 kg/${\mathrm{cm}}^2$. Beyond this the melting point decreased with increasing presure. A triple point at 112 000 kg/${\mathrm{cm}}^2$, 200°C occurred at the junction of the solid I-II line and the melting line. Only electrical resistance type measurements were made. Other transitions might be shown by volume measurements.