dc.contributor.author |
Aksenov S. |
|
dc.contributor.author |
Chukanov N. |
|
dc.contributor.author |
Rusakov V. |
|
dc.contributor.author |
Panikorovskii T. |
|
dc.contributor.author |
Rastsvetaeva R. |
|
dc.contributor.author |
Gainov R. |
|
dc.contributor.author |
Vagizov F. |
|
dc.contributor.author |
Lyssenko K. |
|
dc.contributor.author |
Belakovskiy D. |
|
dc.date.accessioned |
2018-09-19T22:40:59Z |
|
dc.date.available |
2018-09-19T22:40:59Z |
|
dc.date.issued |
2016 |
|
dc.identifier.issn |
2052-5192 |
|
dc.identifier.uri |
https://dspace.kpfu.ru/xmlui/handle/net/145359 |
|
dc.description.abstract |
© 2016 International Union of Crystallography.Vesuvianite containing 5.85 wt% TiO2 from an Alpine-cleft-type assemblage outcropped near Alchuri, Shigar Valley, Northern Areas, Pakistan, has been investigated by means of electron microprobe analyses, gas-chromatographic analysis of H2O, X-ray powder diffraction, single-crystal X-ray structure refinement, 27Al NMR, 57Fe Mössbauer spectroscopy, IR spectroscopy and optical measurements. Tetragonal unit-cell parameters are: a = 15.5326 (2), c = 11.8040 (2) Å, space group P4/nnc. The structure was refined to final R1 = 0.031, wR2 = 0.057 for 11247 I > 2σ(I). A general crystal-chemical formula of studied sample can be written as follows (Z = 2): [8-9](Ca17.1Na0.9) [8]Ca1.0[5](Fe2+ 0.44Fe3+ 0.34Mg0.22) [6](Al3.59Mg0.41) [6](Al4.03Ti2.20Fe3+1.37Fe2+ 0.40) (Si18O68) [(OH)5.84O2.83F1.33]. The octahedral site Y2 is Al-dominant and does not contain transition elements. Another octahedral site Y3 is also Al-dominant and contains Fe2+, Fe3+ and Ti. The site Y1 is split into Y1a and Y1b predominantly occupied by Fe2+ and Fe3+, respectively. The role of the Y1 site in the diversity of vesuvianite-group minerals is discussed. |
|
dc.relation.ispartofseries |
Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials |
|
dc.subject |
27 Al NMR NMR spectroscopy |
|
dc.subject |
crystal chemistry |
|
dc.subject |
IR spectroscopy |
|
dc.subject |
Mössbauer spectroscopy |
|
dc.subject |
vesuvianite |
|
dc.title |
Towards a revisitation of vesuvianite-group nomenclature: The crystal structure of Ti-rich vesuvianite from Alchuri, Shigar Valley, Pakistan |
|
dc.type |
Article |
|
dc.relation.ispartofseries-volume |
72 |
|
dc.collection |
Публикации сотрудников КФУ |
|
dc.relation.startpage |
744 |
|
dc.source.id |
SCOPUS20525192-2016-72-SID84990047401 |
|