caa a22 4500 463217349 CHVBK 20180405153201.0 cr unu---uuuuu 170326e20071201xx s 000 0 eng 10.1007/s00269-007-0189-z doi (NATIONALLICENCE)springer-10.1007/s00269-007-0189-z Thermodynamics of mixing in diopside-jadeite, CaMgSi2O6-NaAlSi2O6, solid solution from static lattice energy calculations [Elektronische Daten] [Victor Vinograd, Julian Gale, Björn Winkler] Static lattice energy calculations (SLEC), based on empirical interatomic potentials, have been performed for a set of 800 different structures in a 2×2×4 supercell of C2/c diopside with compositions between diopside and jadeite, and with different states of order of the exchangeable Na/Ca and Mg/Al cations. Excess static energies of these structures have been cluster expanded in a basis set of 37 pair-interaction parameters. These parameters have been used to constrain Monte Carlo simulations of temperature-dependent properties in the range of 273-2,023K and to calculate a temperature-composition phase diagram. The simulations predict the order-disorder transition in omphacite at 1,150±20°C in good agreement with the experimental data of Carpenter (Mineral Petrol 78:433-440, 1981). The stronger ordering of Mg/Al within the M1 site than of Ca/Na in the M2 site is attributed to the shorter M1-M1 nearest-neighbor distance, and, consequently, the stronger ordering force. The comparison of the simulated relationship between the order parameters corresponding to M1 and M2 sites with the X-ray refinement data on natural omphacites (Boffa Ballaran et al. in Am Mineral 83:419-433, 1998) suggests that the cation ordering becomes kinetically ineffective at about 600°C. Springer-Verlag, 2007 Diopside-jadeite solid solution nationallicence Atomistic simulations nationallicence Activity-composition relations nationallicence Vinograd Victor Institute of Geosciences, University of Frankfurt, Altenhöferallee 1, 60438, Frankfurt, Germany aut Gale Julian Nanochemistry Research Institute, Department of Applied Chemistry, Curtin University of Technology, PO Box U1987, 6845, Perth, WA, Australia aut Winkler Björn Institute of Geosciences, University of Frankfurt, Altenhöferallee 1, 60438, Frankfurt, Germany aut Physics and Chemistry of Minerals Springer-Verlag 34/10(2007-12-01), 713-725 0342-1791 34:10<713 2007 34 269 https://doi.org/10.1007/s00269-007-0189-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00269-007-0189-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Vinograd Victor Institute of Geosciences, University of Frankfurt, Altenhöferallee 1, 60438, Frankfurt, Germany aut NATIONALLICENCE 700 1- Gale Julian Nanochemistry Research Institute, Department of Applied Chemistry, Curtin University of Technology, PO Box U1987, 6845, Perth, WA, Australia aut NATIONALLICENCE 700 1- Winkler Björn Institute of Geosciences, University of Frankfurt, Altenhöferallee 1, 60438, Frankfurt, Germany aut NATIONALLICENCE 773 0- Physics and Chemistry of Minerals Springer-Verlag 34/10(2007-12-01), 713-725 0342-1791 34:10<713 2007 34 269 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer