Interconnection of point defect parameters in solids with bulk properties: A review

TL;DR

This review compares two historical models linking point defect energies in solids to bulk properties, finding that the model based on the isothermal bulk modulus and mean atomic volume aligns better with experimental data across various materials.

Contribution

It provides a comprehensive comparison of two models for defect-bulk property interconnection, highlighting the superior performance of the model based on the isothermal bulk modulus.

Findings

The isothermal bulk modulus model outperforms the shear modulus model.

The models are tested across metals and superionic solids.

The isothermal bulk modulus model shows better agreement with experimental data.

Abstract

Two models have been proposed for the interconnection of the defect Gibbs energy g^i with bulk properties almost 60 and 30 years ago, respectively. The one, proposed by Zener, assumes that g^i can be accounted for the work that goes into straining the lattice and hence it is proportional to the shear modulus of the solid. The other, considers that, since g^i corresponds to an isobaric and isothermal process, it should be proportional to the isothermal bulk modulus and the mean volume per atom. The results of these two models are compared for different processes (defect formation, self-diffusion activation, hetero-diffusion) in a variety of solids including metals (fcc, bcc and tetragonal) as well as solids that exhibit superionic behavior. We find that the latter model does better than the former.