Static elasticity of cordierite I : effect of heavy ion irradiation on the compressibility of hydrous cordierite
Articolo
Data di Pubblicazione:
2014
Citazione:
Static elasticity of cordierite I : effect of heavy ion irradiation on the compressibility of hydrous cordierite / R. Miletich, K.S. Scheidl, M. Schmitt, A.P. Moissl, T. Pippinger, G.D. Gatta, B. Schuster, C. Trautmann. - In: PHYSICS AND CHEMISTRY OF MINERALS. - ISSN 0342-1791. - 41:8(2014), pp. 579-591.
Abstract:
The effect of ion beam irradiations on the elastic properties of hydrous cordierite was investigated by means of Raman and X-ray diffraction experiments. Oriented single crystals were exposed to swift heavy ions (Au, Bi) of various specific energies (10.0-11.1 MeV/u and 80 MeV/u), applying fluences up to 5 × 1013 ions/cm2. The determination of unit-cell constants yields a volume strain of 3.4 × 10-3 up to the maximum fluence, which corresponds to a compression of non-irradiated cordierite at ~480 ± 10 MPa. The unit-cell contraction is anisotropic (e1 = 1.4 ± 0.1 × 10-3, e2 = 1.5 ± 0.1 × 10-3, and e3 = 7 ± 1 × 10-4) with the c-axis to shrink only half as much as the axes within the ab-plane. The lattice elasticity for irradiated cordierite (φ{symbol} = 1 × 1012 ions/cm2) was determined from single-crystal XRD measurements in the diamond anvil cell. The fitted third-order Birch-Murnaghan equation-of-state parameters of irradiated cordierite (V0 = 1548.41 ± 0.16 Å3, K0 = 117.1 ± 1.1 GPa, ∂K/∂P = -0.6 ± 0.3) reveal a 10-11 % higher compressibility compared to non-irradiated cordierite. While the higher compressibility is attributed to the previously reported irradiation-induced loss of extra-framework H2O, the anomalous elasticity as expressed by elastic softening (β a-1, β b-1, β c-1 = 397 ± 9, 395 ± 28, 308 ± 11 GPa, ∂(β-1)/∂P = -4.5 ± 2.7, -6.6 ± 8.4, -5.4 ± 3.0) appears to be related to the framework stability and to be independent of the water content in the channels and thus of the ion beam exposure.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
Cordierite; Equation of state; Heavy-ion irradiation; High-pressure Raman spectroscopy; Single-crystal diffraction; Static compressibility
Elenco autori:
R. Miletich, K.S. Scheidl, M. Schmitt, A.P. Moissl, T. Pippinger, G.D. Gatta, B. Schuster, C. Trautmann
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