Pressure-induced structural transformation in solid xenon studied by Raman spectroscopy

High-pressure transformation from face-centered cubic (fcc) to hexagonal close-packed (hcp) structures of solid xenon has been observed between 5 and 41 GPa in a diamond-anvil cell by Raman spectroscopy. The transverse optic E-2g mode, which is Raman active in the hcp phase, starts to appear around 40 cm(-1) at a pressure of 5 GPa. The Raman frequency increases to 95 cm(-1) at 41 GPa. Moreover, the intensity of the Raman band grows with pressure and shows a remarkable increase around 20 GPa. These vibrational properties were reproduced almost quantitatively by first-principles calculations. The behavior of high-pressure fcc-to-hcp transformation is compared with previous x-ray experiments and theoretical calculations on solid Xe.