An IR absorption calibration for water in minerals
- Author(s)
- Eugen Libowitzky, George R. Rossman
- Abstract
Using IR absorption data from polarized measurements on single-crystal minerals with stoichiometric water contents (in the form of H2O or OH groups in the structure), a linear calibration curve (r2 » 0.98) for water in minerals is established in the form: ei (the integrated molar absorption coeff. in units of cm-2 per mol H2O/L) = 246.6(3753 - u) (u = the mean wavenumber of OH stretching band [in cm-1]). The investigated minerals were: hydrogrossular, analcime, hemimorphite and its dehydrated phase, lawsonite, goethite, diaspore, manganite, mozartite, and pectolite. The influence of hydrogen bonding, leading to increased absorption values with lower OH stretching band energies, is confirmed. Only the use of integrated absorbance values (band areas) results in a linear correlation with water content, whereas linear absorption data (peak heights) are not correlated. The calibration agrees with previously published quant. IR data on staurolite and trace H in pyroxenes. It is also close to the frequently used trend of Paterson (1982). However, some of the previous calibrations of trace H in nominally anhyd. minerals, e.g., kyanite and pyrope, differ appreciably from the correlation derived from stoichiometrically hydrous minerals.
- Organisation(s)
- Department of Mineralogy and Crystallography
- External organisation(s)
- California Institute of Technology (Caltech)
- Journal
- The American mineralogist
- Volume
- 82
- Pages
- 1111-1115
- No. of pages
- 5
- ISSN
- 0003-004X
- DOI
- https://doi.org/10.2138/am-1997-11-1208
- Publication date
- 12-1997
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 104026 Spectroscopy, 105116 Mineralogy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/an-ir-absorption-calibration-for-water-in-minerals(144ca254-ada2-4d26-8202-f54a479767b8).html