Prossima pubblicazione.
Referenza:
▪ Martinelli, A., Lepore, G.O., Bernardini, F., Giaccherini, A., Di Benedetto, F. (2018): The puzzling structure of Cu5FeS4 (bornite) at low temperature. Acta Crystallographica, B74, (in press).
Synopsis:
Several studies have focused on the positions of cations in bornite; however there is still a lack of definitive proof on the ordering of iron. Comparison between high-resolution diffraction data and EXAFS strongly suggests that the preferred location of iron is on two specific sites. Moreover, the high-resolution X-ray powder diffraction revealed that a low-temperature first transition occurs towards a even more puzzling structure, studied on the basis of the room-temperature structure.
The puzzling structure of bornite at low temperature
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
The puzzling structure of bornite at low temperature
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: The puzzling structure of bornite at low temperature
Referenza:
▪ Martinelli, A., Lepore, G.O., Bernardini, F., Giaccherini, A., Di Benedetto, F. (2018): The puzzling structure of Cu5FeS4 (bornite) at low temperature. Acta Crystallographica, B74, (in press).
Abstract
The crystal structure of Cu5FeS4 (bornite) has been investigated using synchrotron X‐ray powder diffraction at temperatures between 10 and 275 K. Diffraction data confirm that bornite crystallizes in the orthorhombic space group Pbca at 275 K. The unit‐cell volume decreases continuously on cooling, but undergoes an abrupt contraction below ∼65 K, where a first‐order Pbca→Pca21 structural transition takes place. The primary active mode yielding the observed ordered structure corresponds to the irreducible representation Γ2−, with wavevector (0,0,0). Pair distribution function analysis shows strong discrepancies between the local and the average structure. The average Fe—S bond length obtained through the EXAFS local probe is consistent with the values independently provided by X‐ray powder diffraction data, strongly supporting the preferred location of Fe.
▪ Martinelli, A., Lepore, G.O., Bernardini, F., Giaccherini, A., Di Benedetto, F. (2018): The puzzling structure of Cu5FeS4 (bornite) at low temperature. Acta Crystallographica, B74, (in press).
Abstract
The crystal structure of Cu5FeS4 (bornite) has been investigated using synchrotron X‐ray powder diffraction at temperatures between 10 and 275 K. Diffraction data confirm that bornite crystallizes in the orthorhombic space group Pbca at 275 K. The unit‐cell volume decreases continuously on cooling, but undergoes an abrupt contraction below ∼65 K, where a first‐order Pbca→Pca21 structural transition takes place. The primary active mode yielding the observed ordered structure corresponds to the irreducible representation Γ2−, with wavevector (0,0,0). Pair distribution function analysis shows strong discrepancies between the local and the average structure. The average Fe—S bond length obtained through the EXAFS local probe is consistent with the values independently provided by X‐ray powder diffraction data, strongly supporting the preferred location of Fe.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: The puzzling structure of bornite at low temperature
Pubblicazione effettuata.
Referenza:
▪ Martinelli, A., Lepore, G.O., Bernardini, F., Giaccherini, A., Di Benedetto, F. (2018): The puzzling structure of Cu5FeS4 (bornite) at low temperature. Acta Crystallographica, B74, 405-415.
Referenza:
▪ Martinelli, A., Lepore, G.O., Bernardini, F., Giaccherini, A., Di Benedetto, F. (2018): The puzzling structure of Cu5FeS4 (bornite) at low temperature. Acta Crystallographica, B74, 405-415.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
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