A new mechanism of anionic substitution in fluoride borates

Rashchenko, Sergey V.; Bekker, Tatyana B.; Bakakin, Vladimir V.; Seryotkin, Yurii V.; Kokh, Alexander E.; Gille, Peter; Popov, Arthur I. und Fedorov, Pavel P. (2013): A new mechanism of anionic substitution in fluoride borates. In: Journal of Applied Crystallography, Bd. 46, Nr. 4: S. 1081-1084

Abstract

A comprehensive study of the BaF2-Ba3(BO 3)2 phase diagram has revealed a significant difference between the two intermediate phases Ba5(BO3)3F and Ba 7(BO3)4-y F2+3y. The latter exhibited (BO 3)3- ↔ 3F- anionic substitution which, unusually, strongly influences the solidus temperature. A comparison of the Ba5(BO3)3F and Ba7(BO3)4-y F2+3y crystal structures, along with consideration of other compounds demonstrating (BO3)3- ↔ 3F- isomorphism, allows for the disclosure of the mechanism of (BO3)3- ↔ 3F - heterovalent anionic substitution in fluoride borates via [(BO 3)F]4- tetrahedral groups being replaced by four fluoride anions. No exception to this mechanism has been discovered among all known phases with (BO3)3- ↔ 3F- substitution.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Geowissenschaften > Department für Geo- und Umweltwissenschaften > Kristallographie und Materialwissenschaft
• Themengebiete: 500 Naturwissenschaften und Mathematik > 550 Geowissenschaften, Geologie
• Sprache: Englisch