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  • Diffusional Relaxation of Quadrupole Interactions of 111In/ Cd Probes in IrIn3 and Related Phases Having FeGa3 Structure
Title: Diffusional Relaxation of Quadrupole Interactions of 111In/ Cd Probes in IrIn3 and Related Phases Having FeGa3 Structure
Nuclear relaxation caused by diffusion of 111 In/Cd probe atoms was measured in four phases having the tetragonal FeGa 3 structure (tP16) using perturbed angular correlation spectroscopy (PAC) and used to gain insight into diffusion processes in phases having more than one diffusion sublattice. The three indide phases studied in this work have two inequivalent and interpenetrating In-sublattices, labeled In1 and In2, and nuclear quadrupole interactions were resolved for probes on each sublattice. The phases are line-compounds with narrow field-widths. Diffusional relaxations, fitted using an exponential damping ansatz , were measured at the two opposing boundary compositions as a function of temperature. “High” and “low” relaxation regimes were observed that are attributed to In-poorer and In-richer compositions, under the reasonable assumption that the atomic motion occurs via an indium-vacancy diffusion mechanism. Relaxation was observed to be greater for tracer atoms starting on In2 sites in the indides immediately following decay of 111 In into 111 Cd, which is attributed to a preference of daughter Cd-tracer atoms and/or indium vacancies to occupy In1 sites. Activation enthalpies for relaxation are compared with enthalpies for self-diffusion in indium metal.  more » « less
Award ID(s):
1809531
PAR ID:
10420857
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Defect and Diffusion Forum
Volume:
420
ISSN:
1662-9507
Page Range / eLocation ID:
73 to 90
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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