These are the data files from the paper :

"Thermodynamic and optical thickness corrections to diffusive radiative transfer 
formulations with application to planetary interiors" by A.M. Hofmeister
Geophysical Research Letters, Volume 41, Issue 9, pages 3074-3080, 16 May 2014

The file Brahinmerged.TXT is absorbance data scaled to 1 mm thickness.
The left column is wavenumbers in cm-1.
The right column is absorption coefficient on a common log basis per mm
The sample is olivine in the Brahin meteorite, which has very little Fe3+

The file Mgomerged.TXT is absorbance data scaled to 1 mm thickness
The left column is wavenumbers in cm-1.
The right column is absorption coefficient on a common log basis per mm
The sample is a cm sized cube from SPi that is very dry.