Diamond as pressure sensor in high‐pressure Raman spectroscopy using sapphire and other gem anvil cells

Abstract

AbstractWe propose a new Raman pressure scale based on the shift with pressure of the fundamental Raman band of micrometer‐sized diamonds. First, we confirmed that the pressure slope of the triply degenerate diamond phonon behaves in a similar fashion to that of the bulk. Our measurements were calibrated Raman against the Sm:YAG fluorescence pressure scale up to 5 GPa using a gasketed sapphire anvil cell. The most relevant features regarding the design of the anvil cell are briefly outlined. Measurements were performed under hydrostatic conditions using 4 : 1 methanol–ethanol as pressure‐transmitting medium. The calibration pressures according to the relationship p(GPa) = 0.356[ν(cm−1) − 1332.3] are considered to be accurate within about 0.1 GPa. The convenience of using micrometer‐sized diamonds as pressure sensors in Raman studies using gem anvil devices is demonstrated with several examples. Copyright © 2003 John Wiley & Sons, Ltd.