PyDII: A python framework for computing equilibrium intrinsic point defect concentrations and extrinsic solute site preferences in intermetallic compounds

TitlePyDII: A python framework for computing equilibrium intrinsic point defect concentrations and extrinsic solute site preferences in intermetallic compounds
Publication TypeJournal Article
Year of Publication2015
AuthorsHong Ding, Bharat Medasani, Wei Chen, Kristin A. Persson, Maciej Haranczyk, Mark D. Asta
JournalComputer Physics Communications
Volume193
118
Pagination118-123
Date Published03/2015
KeywordsExtrinsic solute site preference, Intermetallic compound, Intrinsic point defect, Python
Abstract

Point defects play an important role in determining the structural stability and mechanical behavior of intermetallic compounds. To help quantitatively understand the point defect properties in these compounds, we developed PyDII, a Python program that performs thermodynamic calculations of equilibrium intrinsic point defect concentrations and extrinsic solute site preferences in intermetallics. The algorithm implemented in PyDII is built upon a dilute-solution thermodynamic formalism with a set of defect excitation energies calculated from first-principles density-functional theory methods. The analysis module in PyDII enables automated calculations of equilibrium intrinsic antisite and vacancy concentrations as a function of composition and temperature (over ranges where the dilute solution formalism is accurate) and the point defect concentration changes arising from addition of an extrinsic substitutional solute species. To demonstrate the applications of PyDII, we provide examples for intrinsic point defect concentrations in NiAl and Al3 V and site preferences for Ti, Mo and Fe solutes in NiAl.

DOI10.1016/j.cpc.2015.03.015