OH ABSORPTION COEFFICIENTS OF RUTILE AND CASSITERITE DEDUCED FROM NUCLEAR REACTION ANALYSIS AND FTIR SPECTROSCOPY

Abstract

The OH content of four rutile and two cassiterite single-crystals was studied by nuclear reaction analysis (NRA) and by polarised FTIR microspectroscopy. The OH absorption bands of both minerals are centered around 3300 cm-1th different absorption features. The analytical H2ontent determined by NRA ranges from 70 to 820 wt.ppm. The integrated molar absorption coefficients deduced from the total integrated OH absorbances are equal to 38000 lċmol−1 H2Oċcm−2 for rutile and 65000 lċmol−1 H2Oċcm−2 for cassiterite. For both minerals the absorption coefficients are significantly smaller than those expected from the linear calibration curves given by Paterson (1982) and by Libowitzky and Rossman (1997).