High-pressure in situ investigation of cubanite (CuFe2S3): Electronic structure
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An in situ study of cubanite (CuFe2S3) was performed using energy dispersive X-ray diffraction and Mössbauer spectroscopy in a diamond anvil cell at room temperature and pressures up to 5 GPa. Mössbauer spectra of orthorhombic cubanite show a single iron site with a hyperfine magnetic field that is relatively insentive to pressure, and a centre shift which decreases with pressure at a rate consistent with no significant changes in bonding. Above 3 GPa, however, a nonmagnetic component appears that can be fitted to a single asymmetric quadrupole doublet with a centre shift corresponding to valence between Fe2+ and Fe3+. This is consistent with X-ray diffraction data that show an accompanying transition from the orthorhombic structure to the NiAs structure, where localised electron transfer could occur across pairs of face-shared octahedra or extended electron delocalisation could occur along sheets of face- and edge-shared octahedra.
KeywordsOrthorhombic Structure Electron Delocalisation Hyperfine Magnetic Field Diamond Anvil Cell Quadrupole Doublet
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- C.A. McCammon, J. Zhang, R.M. Hazen and L.W. Finger, Am. Mineral. 77(1992)937.Google Scholar
- L. Merrill and W.A. Bassett, Rev. Sci. Instr. 45(1974)290.Google Scholar
- L.J. Cabri, S.R. Hall, J.T. Syzmanski and J.M. Stewart, Can. Mineral. 12(1973)33.Google Scholar
- C.A. McCammon, in:Recent Trends in High Pressure Research, ed. A.K. Singh (Oxford & IBH, New Delhi, 1992) p. 824.Google Scholar
- C.A. McCammon, in:High Pressure Science and Technology, ed. S.C. Schmidt (American Institute of Physics, New York) in press.Google Scholar
- P. Imbert and M. Wintenberger, Bull Soc. Fr. Minéral. Cristallogr. 90(1967)299.Google Scholar
- S.V. Karyagin, Sov. Phys. Solid State 8(1966)391.Google Scholar
- D.L. Williamson, in:Mössbauer Isomer Shifts, eds. G.K. Shenoy and F.E. Wagner (North-Holland, Amsterdam, 1978) p.317.Google Scholar
- H.G. Drickamer, R.W. Vaughn and A.R. Champion, Accounts Chem. Res. 2(1969)40.Google Scholar
- H.E. King, Jr. and C.T. Prewitt, Acta Cryst. B38(1982)1877.Google Scholar
- H. King, D. Virgo and H.K. Mao, Ann. Rept. Geophys. Lab. 77(1978)830.Google Scholar