| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
High Entropy Materials: Concentrated Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond V
|
| Presentation Title |
New Insight into the Disordering Mechanism in Fluorite-Related Ceramics |
| Author(s) |
Maik K. Lang |
| On-Site Speaker (Planned) |
Maik K. Lang |
| Abstract Scope |
Structural disorder plays a critical role in technological applications to tailor specific functionalities, such as ionic conductivity in fuel cells or batteries. Previous studies have shown that the atomic arrangements of many disordered crystalline materials are not random nor are they represented by the long-range structure observed from diffraction experiments. Structural heterogeneity at different length-scales appears to be a general characteristic of disordered materials. This presentation reviews recent neutron scattering experiments on fluorite-related ceramics with complex disordering behavior. Structural information from pair distribution functions with sensitivity to both cation and anion sublattices were utilized to investigate in detail the disordering process of A2B2O7 pyrochlore oxides. The order-disorder transformation can be understood as a rearrangement of atomic-scale building blocks yielding a configurationally averaged long-range structure. The atomic arrangement within the disordered phase involves a high level of order which can be rationalized based on a set of fundamental chemical rules. |