Spectroscopy of II–VI nanocrystals at high pressure and high temperature

We review experimental measurements of CdS, CdSe, and CdS_xSe_{1 ? x} nanocrystals which address the properties and phase stability of both powder and embedded nanoparticles under extreme conditions. We address the high pressure phase transition of wurtzite or zincblende phase to the rock salt structure; the high temperature solid to liquid phase transition; and the homogeneous nucleation of nanoparticles in glass from dissolved reactants. We also review the use of high pressure optical measurements to study electronic states.