Referenza:
▪ Kazheva, O.N., Zubkova, N.V., Schäfer, Ch., Chukanov, N.V., Pekov, I., Britvin, S.N., Pushcharovsky, D. (2021): The Pseudobrookite Group: Crystal Chemical Features of the Armalcolite Fe2+ Analogue. Doklady Earth Sciences, 497, 305-309.
Abstract:
The crystal structure of a potentially new mineral, the Fe2+-dominant analogue of armalcolite with the idealized formula Fe2+Ti2O5 has been solved. The sample studied originates from a pneumatolytic association related to the lamproite complex of SE Spain. The mineral is orthorhombic, space group Cmcm, the unit-cell parameters are a = 3.7325(1) Å, b = 9.7649(4) Å, c = 9.9902(3) Å, V = 364.12(2) Å3. The crystal-chemical formula M1(Mg0.19Fe2+0.25Fe3+0.26Ti0.30)2.86+[M2(Ti0.65Fe3+0.27Fe2+0.08)3.57+]2O5 (Z = 4) is in good agreement with the chemical composition of the mineral.
NdR: general formula of the pseudobrookite group: M(1)M(2)2O5, the M cations (Mg2+, Fe2+, Fe3+, and Ti4+) occupy two independent positions M(1) and M(2) (Wykoff positions 4c and 8f, respectively) [5, 7]. These cations have octahedral coordination.
Pseudobrookite group: Crystal chemical features of the armalcolite Fe2+ analogue
- Marco E. Ciriotti
- Messaggi: 31675
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Pseudobrookite group: Crystal chemical features of the armalcolite Fe2+ analogue
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»
Chi c’è in linea
Visitano il forum: Bing [Bot] e 44 ospiti