|About this Abstract
|MS&T23: Materials Science & Technology
|Phase Transformations in Ceramics: Science and Applications
|Using Total Scattering Techniques to Explore Fundamental Aspects of the Structural Organization in Weberite-type Tantalate Oxides
|Igor M. Gussev, Gianguido Baldinozzi, Eric O’Quinn, Joerg Neuefeind, Maik Lang
|On-Site Speaker (Planned)
|Igor M. Gussev
Weberite-type tantalate oxides (A3TaO7) are promising candidates for many energy-related applications. However, there is only a limited understanding of how their atomic-scale structure changes under exposure to extreme conditions. We performed neutron total scattering experiments across a compositional range of oxides and analyzed the real space, short-range pair correlation functions to establish evidence that their local atomic arrangements adopt organization different from their well-known long-range structure. This finding appears to be a general phenomenon for a range of weberite-type oxides, spanning from fully ordered (Pr3TaO7) to fully disordered (Yb3TaO7). Furthermore, comparing short- and long-range structural behaviors across the compositional series has revealed a complex organization of structural length scales: the short-range analysis suggests a strong dependence on the ionic radius of the A-site cation and the distortion of a local structural motif that monotonically increases across the compositional series, while the long-range analysis confirmed the existence of three distinct structures.