AsS melt under pressure: one substance, three liquids.
An in situ high-temperature--high-pressure study of liquid chalcogenide AsS by x-ray diffraction, resistivity measurements, and quenching from melt is presented. The obtained data provide direct evidence for the existence in the melt under compression of two transformations: one is from a moderate-viscosity molecular liquid to a high-viscosity nonmetallic polymerized liquid at P approximately 1.6-2.2 GPa; the other is from the latter to a low-viscosity metallic liquid at P approximately 4.6-4.8 GPa. Upon rapid cooling, molecular and metallic liquids crystallize to normal and high-pressure phases, respectively, while a polymerized liquid is easily quenched to a new AsS glass. General aspects of multiple phase transitions in liquid AsS, including relations to the phase diagram of the respective crystalline, are discussed.
Institute for High Pressure Physics, Russian Academy of Sciences, 142190, Troitsk Moscow region, Russia.
V V
VV
Brazhkin
Y
Y
Katayama
M V
MV
Kondrin
T
T
Hattori
A G
AG
Lyapin
H
H
Saitoh