Synthesis and crystal structure of C2/c Ca(Co, Mg)Si2O6 pyroxenes: effect of the cation substitution on cell volume. (2nd January 2018)

• Record Type: Journal Article
• Authors: Gori, C.; Tribaudino, M.; Mantovani, L.; Gatta, G. D.; Delmonte, D.; Gilioli, E.; Mezzadri, F.; Calestani, G.
• Is Part Of: Mineralogical magazine. Volume 81:Number 5(2017)
• Page Start: 1129
• Page End: 1139
• Publication Date: 2018-01-02
• Subjects: pyroxene, -- cobalt, -- site substitution, -- crystal chemistry; Mineralogy -- Periodicals; Mineralogy -- Great Britain -- Periodicals; 549.05
• DOI: 10.1180/minmag.2016.080.160
• Languages: English
• ISSNs: 0026-461X

Abstract

Abstract: A series of clinopyroxenes along the CaMgSi2 O6 –CaCoSi2 O6 join was synthesized by quenching from melts at 1500°C and subsequent annealing at 1250°C (at 0.0001 GPa). This protocol proved to be the most effective to obtain homogenous, impurity-free and stoichiometric pyroxenes. Electron microprobe analyses in energy dispersive mode were conducted and single-crystal X-ray diffraction data were collected on Ca (Co x Mg1- x )Si2 O6 pyroxenes with x = 0.2, 0.4, 0.5, 0.6. Effects of cation substitution at the M 1 site are described. The experimental findings of this study allow us to extend the comparative analysis of the structural features of pyroxenes with divalent cations at the M 1 and M 2 sites.