Crystal structure of vanuralite

database, nuove specie, discrediti,
ridefinizioni, classificazioni, ecc.
Rispondi
Avatar utente
Marco E. Ciriotti
Messaggi: 24002
Iscritto il: ven 25 giu, 2004 11:31
Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
Contatta:

Crystal structure of vanuralite

Messaggio da Marco E. Ciriotti » mar 04 lug, 2017 10:17

Prossima pubblicazione.

Referenza:
▪ Plášil, J. (2017): Crystal structure of vanuralite, Al[(UO2)2(VO4)2](OH)·8.5H2O. Zeitschrift für Kristallographie - Crystalline Materials, 232, (in press).

Abstract:
Vanuralite, Al[(UO2)2(VO4)2](OH)·8.5H2O, is a rare supergene uranyl vanadate that forms during hydration-oxidation weathering of uraninite in oxide zones of U deposits. On the basis of single-crystal X-ray diffraction data it is monoclinic, space group P21/n, with a=10.4637(10), b=8.4700(5), c=20.527(2) Å, β=102.821(9)°, V=1773.9(3) Å3 and Z=4, Dcalc.=3.561 g cm−3. The structure of vanuralite (R=0.058 for 2638 unique observed reflections) contains uranyl vanadate sheets of francevillite topology of the composition [(UO2)2(VO4)2]2−. Sheets are stacked perpendicular to c, and an interstitial complex [6]Al(OH)(H2O)4(H2O)4.5; adjacent structural sheets are linked through an extensive network of hydrogen bonds. Vanuralite is the most complex mineral among uranyl vanadates, with 961 bits/cell. The scarcity of occurrences is probably caused by the less common combination of elements present in the structure, as well as the relatively high complexity of the structure (compared to related minerals), arising namely from the complicated network of H-bonds.
Marco E. Ciriotti

«Things are interesting only in so far as they relate themselves to other things»

Avatar utente
Marco E. Ciriotti
Messaggi: 24002
Iscritto il: ven 25 giu, 2004 11:31
Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
Contatta:

Re: Crystal structure of vanuralite

Messaggio da Marco E. Ciriotti » mer 29 nov, 2017 13:18

Pubblicazione avvenuta.

Referenza:
▪ Plášil, J. (2017): Crystal structure of vanuralite, Al[(UO2)2(VO4)2](OH)·8.5H2O. Zeitschrift für Kristallographie - Crystalline Materials, 232, 807-814.
Marco E. Ciriotti

«Things are interesting only in so far as they relate themselves to other things»

Rispondi

Chi c’è in linea

Visitano il forum: Bing [Bot] e 4 ospiti