Tuesday 9 January 2018

N8 Materials Modelling Meeting - York

The Annual N8 HPC/CCP5/UKCP, "New Horizons in Atomistic Simulations", one day network meeting, at York brought together experts in quantum and atomistic simulations of materials.

Predicted TEM diffraction pattern for Methylammonium Lead Iodide
Robyn Ward, presented her recent work, in collaboration with Christopher Handley, Colin Freeman, and John Harding, on the prediction of rare earth element dynamics within perovskite materials, and the prediction of transition electron spectra, and the determination of the magnitude and phase of the octahedral tilts in these simulations. This work is significant as it now allows us to connect simulation to experimental spectra, and offer insight into the atomic scale dynamics of these materials which is not seen by the experimental analysis techniques. 

Keynote presentations included:

Andrew Morris, from the Department of Metallurgy and Materials at the University of Birmingham presented his work on Ex nihilo Discovery and Design of Energy Materials. In particular Andrew focused on the use of computers to design new battery materials, and the use of quantum mechanical simulations to predict materials for the task rapidly. The challenge he presented is how to rapidly screen material structures and determine by simulation their battery properties (voltages and energy density). In particular Andrew makes use of AIRSS, ab initio random structure searching, which allows him to find the optimal crystal structure for a given stoichiometry for a novel material.

Steve Parker, from the University of Bath, presented his work on the atomistic simulation of interfaces. His main focus was on the role and composition of the interfaces in energy materials, and the mechanisms of thermal and atom transport. His simulations utilised both force fields and quantum mechanics to perform multiscale modelling. Using these methods he demonstrated the ability of simulations to predict the morphology of surfaces and in turn nano-particles. One important issue was the influence of impurities upon oxygen diffusion across grain boundaries. This is relevant to improving the lifetime of the nuclear fuel uranium dioxide. A future challenge is to investigate the heterointerfaces which are significant when we consider capacitor materials that form a core-shell structure.

Dominik Jochym, from the STFC Rutherford Appleton Laboratory presented some exciting work on computational Muon-Spin simulation by Density Functional Theory. Muons allow for the probing of the electron density and spin states, and for probing the magnetic fields of novel materials. The capability of predicting from ab initio such spectra opens up new avenues for understanding the local chemistry of materials and how we might design materials for future technological challenges.