Abstract
The thermal behaviour of β-anhydrite CaSO4 has been investigated to 1,263 K in-situ real-time using laboratory parallel-beam X-ray powder diffraction data. The cell parameters expanded anisotropically, the c axis being the “softest”. This behaviour is due to the deformation of the CaO8 polyhedron. In fact the two longest, independent, Ca–O bond distances show a significant component along the z direction.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Breese NE, O’Keeffe M (1991) Bond-valence parameters for solids. Acta Cryst B47:192–197
Downs RT, Gibbs GV, Bartelmehs KL, Boisen Jr MB (1992) Variations of bond lengths and volumes of silicate tetrahedral with temperature. Am Min 77:751–757
Evans Jr HT (1979) The thermal expansion of anhydrite to 1000°C. Phys Chem Minerals 4:77–82
Fei Y (1995) Thermal expansion. In: Ahrens TJ (ed) Mineral physics and crystallography: a handbook of physical constants, vol 2. American Geophysical Union, Washington, pp 29–44
Finger LW, Cox DE, Jephcoat AP (1994) A correction for powder diffraction peak asymmetry due to axial divergence. J Appl Cryst 27:892–900
Hawthorne FC, Ferguson RB (1975) Anhydrous sulphates. II. Refinement of the crystal structure of anhydrite. Can Mineral 13:289–292
Khan AA (1976) Computer simulation of thermal expansion of non-cubic crystals: forsterite, anhydrite and scheelite. Acta Cryst A32:11–16
Kirfel A, Will G (1980) Charge density in anhydrite, CaSO4, from X-ray and neutron diffraction measurements. Acta Cryst B36:2881–2890
Larson AC, Von Dreele RB (2000) GSAS-General Structure Analysis System. Los Alamos National Laboratory Report No. LAUR 86–748. Los Alamos National Laboratory, Los Alamos
Morikawa H, Minato I, Tomita T, Iwai S (1975) Anhydrite: a refinement. Acta Cryst B31:2164–2165
Reeber RR, Goessel K, Wang K (1995) Thermal expansion and molar volume of MgO, periclase, from 5 to 2900 K. Eur J Mineral 7:1039–1047
Strunz H, Nickel EH (2001) Strunz mineralogical tables, 9th edn. Schweizerbart’sche, Stuttgard, 870 p
Thompson P, Cox DE, Hastings JB (1987) Rietveld refinement of Debye-Scherrer synchrotron X-ray data from Al2O3. J Appl Cryst 20:79–83
Toby BH (2001) EXPGUI, a graphical user interface for GSAS. J Appl Cryst 34:210–213
Von Dreele RB (1997) Quantitative texture analysis by Rietveld refinement. J Appl Cryst 30:517–525
Young RA. (1993) Introduction to the Rietveld method. In: Young RA (ed) The Rietveld method. Oxford Science, Oxford, pp 1–38
Acknowledgments
We thank F. Scordari, two anonymous referees, and Editor P.C. Burnley for their constructive reviews of the paper. This work was supported by Università di Roma “La Sapienza”.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Ballirano, P., Melis, E. Thermal behaviour of β-anhydrite CaSO4 to 1,263 K. Phys Chem Minerals 34, 699–704 (2007). https://doi.org/10.1007/s00269-007-0186-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00269-007-0186-2