Naslov
57^Fe-Mossbauer spectroscopy on natural eosphorite-childrenite-ernstite samples
(57^Fe-Moessbauer spectroscopy on natural eosphorite-childrenite-ernstite samples)

Autori
Da Costa, Geraldo Magela ; Scholz, Ricardo ; Karfunkel, Joachim ; Bermanec, Vladimir ; De Sa Carneiro Chaves, Mario Luiz

Izvornik
Physics and chemistry of minerals (0342-1791) 31 (2005), 10; 714-720

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
eosphorite; childrenite; ernstite; pegmatite; Moessbauer spectra; Brazil

Sažetak
Samples of the eosphorite-childrenite [(Mn^2+, Fe^2+)AlPO_4(OH)2H_2O] series from Divino das Laranjeiras and Aracuai(Minas Gerais State) and Parelhas (Rio Grande do Norte State) pegmatites have been investigated by X-ray diffraction, microprobe analysis and Moessbauer spectroscopy at 295 and 77K. The Moessbauer spectra of ernstite [(Mn^2+, Fe^3+)AlPO_4(OH)_2-xO_x] showed the existance of ferric ions seem to be located in both sites, and no Fe^3+ could be detected. The interpretation of the Moessbauer spectra of both, oxidised and nonoxidised samples, is difficult because the hyperfine parameters of these minerals are rather similar, rendering it difficult to make proper site assignments.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA