R1: Characterization and description of minerals (Joint Session with The Gemmological Society of Japan)

[R1-02] Compositional dependence of EFG tensor of Fe²⁺ in M1site of Ca-rich pyroxene

Daiki Fukuyama¹, *Keiji Shinoda¹, Yasuhiro Kobayashi² (1. Osaka City Univ. Sci., 2. KURNS)

Keywords:Mössbauer spectroscopy, electric field gradient tensor, Ca-rich pyroxene

Fe²⁺ ions which occupy M1 and M2 sites of pyroxene give similar and overlapping quadrupole doublet in Mössbauer spectra. Electric field gradient tensor (EFG) is important for reliable peak analyses of Mössbauer spectra include M1 and M2 doublets. Mössbauer spectra of crystallograhically oriented thin section of Ca-rich pyroxene (diopside, augite and hedenbergite) were measured to reveal compositional dependence of EFG tensor of Fe²⁺ in M1site of Ca-rich pyroxene.