Cormac Henry Toher
Duke University, USA
Abstract: The AFLOW framework for computational materials design integrates modules to generate new materials structures using crystallographic prototypes with routines to analyze symmetry and thermodynamic stability, calculate thermo-mechanical properties and perform automated error correction of DFT calculations. The data generated using AFLOW are available online at aflow.org and are programmatically accessible via the AFLOW REST-API and AFLUX Search-API.
Analysis of the dependence of formation enthalpy on the number of species using data extracted from the AFLOW data repository shows that the gain in formation entropy exceeds the gain in formation enthalpy as more species are added to the mixture, demonstrating the importance of disorder in the formation of multicomponent materials. Disordered materials are difficult to model directly using first principles calculations. Therefore, descriptors and thermodynamic models have been developed using data from ensembles of ordered calculations in the AFLOW data repository to predict the synthesizability of new disordered materials such as metallic glasses and high entropy carbides using the thermodynamic density of states, as well as to predict the transition temperatures and miscibility gaps for high entropy alloys. AFLOW data is also being employed to train machine-learning models to predict properties ranging from the electronic band gap to thermo-mechanical properties such as the bulk modulus and Debye temperature. These machine-learning models are now available for use via interactive online applications on the aflow.org web portal at aflow.org/aflow-ml, and are programmatically accessible via the new AFLOW-ML API.
Prof. Toher is an Assistant Research Professor in the Department of Mechanical Engineering and Materials Science in Duke University, and is Associate Director of the Center for Autonomous Materials Design. He obtained his PhD degree in Physics from Trinity College Dublin, Ireland in 2008 under the supervision of Prof. Stefano Sanvito. He then joined the group of Prof. Gianaurelio Cuniberti in TU Dresden, Germany as a postdoctoral researcher. He joined the group of Stefano Curtarolo in the Center for Materials Genomics/Center for Autonomous Materials Design in Duke University in 2013. He was appointed as a research professor in the Department of Mechanical Engineering and Materials Science in 2015, and as Associate Director of the Center for Autonomous Materials Design in 2019. His research includes the automation of calculations of the thermal and mechanical properties of materials, the development of descriptors for the formation and stability of disordered materials, and the development of machine learning algorithms trained on computational materials science data.