Autori: S. Constantinescu , Gh. Udubasa and S. Calogero

Editorial: Journale de Physique I France, 7, p.777_784, 1997.

Rezumat:

Autorii au obtinut spectre Mössbauer pe doua probe caracteristice , obtinute din doua deposite mineraliere diferite din Carpatii Romanesti. Folosind un program specializat de calcul al parametrului spectral de despicare cuadrupolara QSCOMP, dubletii observati au fost atribuitiionilor fero si feri din pozitiile octaedrale. Analiza rafinata a parametrilor spectrali ne-a permis caracterizarea ambelor stari de oxidare a configuratiilor electronice si a simetriei de coordinatie cu distorsiunile locale si a ocupantelor ionilor constitutivi de fier.
Diferentele dintre parametrii spectrali, observate la cele doua probe studiate si careaduc date despre abundenta, deformatia locala si ocupanta fierului octaedral, sunt discutate si corelate cu conditiile diferite de geneza ale celor doua depozite de pumpelit. The authors obtained the 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.

Cuvinte cheie: 91.60.-x, Proprietati fizice ale rocilor si mineralelor, 76.80.+y, efect Mössbauer , alte spectroscopii // 91.60.-x, Physical properties of rocks and minerals, 76.80.+y, Mössbauer effect, other gamma-ray spectroscopy

URL: http://www.edpsciences.com/articles/jp1/abs/1997/06/ajp10604/ajp10604.html