J. Phys. I France 7 (1997) 777-784
57Fe Mössbauer Spectroscopy on Two Romanian Carpathian PumpellyitesS. Constantinescu1, Gh. Udubasa2 and S. Calogero3
1 Institute of Physics and Technology of Materials, PO Box Mg-07, Bucharest, Romania
2 Geological Institute of Romania, 78344, Bucharest, Romania
3 Universita Ca'Foscari, Dipartamento di Chimica-Fisica, 30123 Venezia, Italy
(Received 13 January 1997, revised 20 February 1997, accepted 8 March 1997)
The authors obtained the Fe 57 Mössbauer spectra of two pumpellyite samples obtained from two different mineral sources in the Romanian Carpathians. Using a specialized computation program of the quadrupole splitting spectral parameter, QSCOMP, the observed quadrupole doublets were attributed to the ferric and ferrous ions in octahedral sites. The refined analysis of spectral parameters permitted us to characterize both the oxidation state, the electronic configuration and the coordination symmetry with the distortions and occupancies of pumpellyite constituting iron ions. The differences of the spectral parameters giving the data of the iron abundance, the chemical iron-oxygen bonds, the deformation and occupancies of iron octahedra, observed at the two studied samples, are discussed and correlated by the different genesis conditions of two pumpellyite-bearing occurrences.
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