Xianwu Bi

Raman spectroscopic characterization of CH4 density over a wide range of temperature and pressure

The positions of the CH 4 Raman ν 1 symmetric stretching bands were measured in a wide range of temperature (from −180 °C to 350 °C) and density (up to 0.45 g/cm 3 ) using high-pressure optical cell and fused silica capillary capsule. The results show that the Raman band shift is a function of both methane density and temperature; the band shifts to lower wavenumbers as the density increases and the temperature decreases. An equation representing the observed relationship among the CH 4 ν 1 band position, temperature, and density can be used to calculate the density in natural or synthetic CH 4 -bearing inclusions.