Single‐crystal elastic properties of omphacite‐C2/c by Brillouin spectroscopy

摘要: Single-crystal Brillouin scattering measurements of elastic moduli were performed on an eclogitic omphacite (space group C2/c) with chemical composition close to the diopside (CaMgSiO2O6, 29.9 mol %)-jadeite (NaAlSi2O6, 57.8 %) join. Prom 13 measured under ambient conditions we calculate adiabatic bulk modulus, KS = 130.8 ±0.5 GPa, and shear μ 79.2 ± 0.2 GPa. The magnitudes all longitudinal (C11, C22, C33) are inferred be influenced primarily by MgO6 CaO8, or M polyhedra. Although silica tetrahedra extremely stiff, great rotational freedom these polyhedra yields a mechanical unit (tetrahedral chains) which is relatively compliant. Virtually intermediate in value those for Jadeite. Most omphacitic pyroxene can estimated within several percent interpolation between end member weighted according molar percentages