| About this Abstract |
| Meeting |
2010 TMS Annual Meeting & Exhibition
|
| Symposium
|
Computational Thermodynamics and Kinetics
|
| Presentation Title |
Explaining the Change in Diffusion Mechanism in the Series of L12 Phases In3R (R= Rare-Earth) |
| Author(s) |
John P. Bevington, Matthew O, Zacate, Gary S. Collins |
| On-Site Speaker (Planned) |
John P. Bevington |
| Abstract Scope |
Recent experiments revealed a remarkable change in the mechanism of diffusion for atoms on the In-sublattice along a series of In<sub>3</sub>R line compounds having L1<sub>2</sub> structure [Phys. Rev. Lett. 102, 155901 (2009)]. Experiments were carried out on pairs of samples with opposing boundary compositions (slightly In-rich and In-poor). Whereas light lanthanide indides (R= La, Ce, Pr, Nd) exhibited higher jump frequencies for In-rich samples, heavy lanthanide indides had higher jump frequencies for In-poor samples. Since, at given temperature, R-vacancy (In-vacancy) concentrations can only increase (decrease) monotonically with increasing In composition, it was concluded that the dominant diffusion mechanisms involve R-vacancies (In-vacancies) in the light (heavy) lanthanide indides. To explain this remarkable change in behavior, calculations of point defect energies along the entire lanthanide tri-indide series are being carried out using the full-potential, all-electron program WIEN2k, with results to be reported at the meeting. |
| Proceedings Inclusion? |
Definite: A CD-only volume |