IMPROVED CALIBRATION CURVE FOR THE SM2+-BAFCL PRESSURE SENSOR

The pressure sensor proposed by Shen, Gregorian & Holzapfel [High Press. Res. (1991). 7, 73 75], based on the pressure-dependent shift of the luminescence line due to the 5D0-F-7(0) electronic transition of Sm2+ in a matrix of BaFCI, has been tested in a diamond-anvil cell and calibrated against the R1-R2 doublet shift of ruby and the known NaCl equation of state, in the pressure range between 0.0001 and 4.3 GPa. The parabolic dependence of the shift from the pressure can be approximated by the equation DELTA(nm) = 1.46P - 0.047P2, where the shift, DELTA, is in nm and the pressure, P, in GPa. The estimated error in the pressure measurements is 5%. The Sm2+:BaFCl luminescence sensor can be advantageously used in the low to moderate pressure range (0.0001-5 GPa or more).