Short-range order in tourmaline: A vibrational spectroscopic approach to elbaite
2012 (English)In: Physics and chemistry of minerals, ISSN 0342-1791, E-ISSN 1432-2021, Vol. 39, no 10, 811-816 p.Article in journal (Refereed) Published
Polarized Fourier-transform infrared and Raman spectra were acquired on an elbaite sample previously characterized by electron- and ion microprobe analysis, X-ray diffraction and structure refinement. Spectra from the two vibrational spectroscopy techniques reveal a close similarity in the OH-stretching region, with three main absorption bands strongly polarized in the c-axis direction. By means of bond-valence theory arguments, the observed OH bands are interpreted and assigned to specific local cation arrangements around the O1 (≡W) and O3 (≡V) anion sites. In combination with the relatively simple composition of the studied sample, bond-valence constraints are used to identify stable anion-cation arrangements, which permit the occurrence of short-range ordering to be assessed. Evidence for nearly complete short-range order at the O1 site, with the stable arrangements Y(LiAlAl) 0. 6- W(OH) 0. 6 and Y(LiLiAl) 0. 4- W(F) 0. 4, are presented. These two local arrangements can be further expanded to obtain the larger ordered clusters [ W(OH)- Y(LiAl 2)- V(OH) 3- Z(Al) 6] 0. 6 and [ W(F)- Y(Li 2Al)- V(OH) 3- Z(Al) 6] 0. 4.
Place, publisher, year, edition, pages
2012. Vol. 39, no 10, 811-816 p.
Bond-valence theory, Elbaite, Infrared spectroscopy, Raman spectroscopy, Short-range ordering, Tourmaline
Earth and Related Environmental Sciences
Research subject Earth Science with specialization in Mineral Chemistry, Petrology and Tectonics
IdentifiersURN: urn:nbn:se:uu:diva-186013DOI: 10.1007/s00269-012-0536-6ISI: 000310539600004OAI: oai:DiVA.org:uu-186013DiVA: diva2:572634