April 2020 – Materials Virtual Lab

April 22, 2020April 22, 2020News, Publications

Random Forest Models for Coordination Environment from XANES

Chen Zheng’s and Chi Chen’s paper on “Random Forest Models for Accurate Identiﬁcation of Coordination Environments from X-Ray Absorption Near-Edge Structure” has just been published in the second issue of the Cell Press journal Patterns! Analyzing coordination environments using X-ray absorption spectroscopy has broad applications in solid-state physics and material chemistry. Here, we show that random forest models trained on 190,000 K-edge XANES can directly identify the main atomic coordination environment with a high accuracy of 85.4%. More importantly, we show that the random forest models can be used to predict coordination environments from experimental K-edge XANES with minimal loss in accuracy. Check out the work here.

April 5, 2020Publications

Genetic algorithm-guided deep learning of grain boundary diagrams

We are proud co-authors of an article published in Materials Today on “Genetic algorithm-guided deep learning of grain boundary diagrams”. Grain boundaries (GBs) often control the processing and properties of polycrystalline materials. In this work, we combine isobaric semi-grand canonical ensemble hybrid Monte Carlo and molecular dynamics (hybrid MC/MD) simulations with a genetic algorithm and deep neural networks (DNN) to predict complexion diagrams. The DNN prediction (work by Yunxing Zuo of MAVRL) is ~108 faster than atomistic simulations, enabling the construction of the property diagrams for millions of distinctly different GBs of ﬁve DOFs. Excellent prediction accuracies have been achieved for not only symmetric-tilt and twist GBs, but also asymmetric-tilt and mixed tilt-twist GBs. The data-driven prediction of GB properties as function of temperature, bulk composition, and ﬁve crystallographic DOFs (i.e., in a 7D space) opens a new paradigm.