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The structure of niobium and tantalum oxides processed by concentrated light flux
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Palatnikov M., Shcherbina O., Sidorov N. and Bormanis K.

Abstract. The article reports on significant changes occurring in the structure under treatment of Nb2O5 and Та2O5 ceramics by a concentrated light flux (CLF). The changes comprise, in particular, appearance of micro- and nanostructures, as well as changing type of chemical bonding and coordination number of polyhedrons. These structural changes manifest themselves in the corresponding changes in the physical properties. The influences of the CLF on the Nb2O5 and Та2O5 ceramics turn out to be different. The number of nanosize structures appearing in the Та2O5 ceramics is higher, while the changes in the chemical bonding and the coordination of polyhe-drons are different. The differences observed by us are explained by differing melt-ing temperatures of Nb2O5 and Та2O5 and degree of covalence of the chemical bonds Nb–O and Ta–O.

Keywords: niobium and tantalum oxides, structure, concentrated light flux, Raman scattering

PACS: 78.30.Ly, 81.05.Je
UDC: 535.4, 538.9
Ukr. J. Phys. Opt. 13 207-214
doi: 10.3116/16091833/13/4/207/2012

Received: 09.09.2012

Анотація. У роботі виявлено суттєві зміни структури внаслідок обробки керамік Nb2O5 і Та2O5 концентрованим потоком світла. Ці зміни полягають у появі мікро- і наноструктур, зміні типу хімічного зв’язку, координаційного числа та ін. Зміни структури виявляються у змінах фізичних властивостей. Впливи концентрованого потоку світла на кераміки Nb2O5 і Та2O5 різні. Зокрема, кількість нанорозмірних структур, що з’являються в кераміці Та2O5, вища, а зміни хімічного зв’язку і координаційних чисел – різні. Ці відмінності пояснюються відмінностями температур плавлення керамік Nb2O5 та Та2O5 і ступеня ковалентності хімічних зв’язків Nb–O і Ta–O.
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