This repository contains the key raw data discussed in the manuscript:

Ab Initio Molecular-Dynamics Simulation of Neuromorphic Computing in Phase-Change Memory Materials
J. M. Skelton, D. Loke, T. H. Lee and S. R. Elliott
ACS Applied Materials & Interfaces
DOI: 10.1021/acsami.5b01825

General:

The files in this repository provide the minimal raw data required to reproduce the analysis and discussion given in the paper. For brevity, and due to the size of some of the files, we have not been able to include all the raw data generated during the study (e.g. the complete set of molecular-dynamics trajectories and data discussed in the SI). Any data from the paper which is not available in this repository may be requested from the authors.

File-naming convention:

The files in this archive are generally named according to the following prefixing convention: 
[Dep | Pot]_[Post Spike Type]
The first part indicates whether the data is from the depression (“Dep”) or potentiation (“Pot”) sequence. The second part denotes the post-spike type (i.e. no overlapping post spikes, or post spikes overlapping with the first, second or third pre-spike pulses).
The exception to this is the ring-analysis data (see below) from the amplitude and pulse-width test sequences shown in Fig. 2 in the text, which do not involve pre- and post-spike pulses and so are simply prefixed with “PulseAmplitude” and “PulseWidth”, respectively.

Available data:

1. MDTrajectories.tar.gz
This archive contains the molecular-dynamics trajectories for the optimised depression and potentiation pulse sequences described in the manuscript. The coordinates and simulation-cell parameters are in the fixed-cell Animated XCRysDen format described at http://www.xcrysden.org/doc/XSF.html (last checked 18/06/2015).The files can be viewed with the VMD software (http://www.ks.uiuc.edu/Research/vmd/, last checked 18/06/2015)
For both sequences, there are “initial”, "pulse" and "rest" parts, several of which make up the complete subsequences with different post-spike timings. The file "Sequences.txt", included in the archive, details which trajectory files must be combined for each subsequence.
The files are named according to the following convention: [Dep | Pot]_[Subsequence Part]_[Post Spike Type].axsf. The first and last components have the same meanings as outlined in the file-naming convention note above. The middle descriptor indicates which part of a subsequence the trajectory corresponds to (i.e. the initial rest phase or the first/second/third pulse or rest phases).
The trajectories and index file are bundled into a single TAR archive compressed with the GZip algorithm. This can be decompressed and unpacked with the tar utility on Linux and MacOS, or the free PeaZip software on Windows (http://peazip.sourceforge.net/; last checked 18/06/2015).
As the trajectory files consume a considerable amount of storage space, we have not included those from the various test sequences described in the text/SI. As noted above, these can be made available on request.

2. *-OrderAnalysis.csv
Contain the raw data from the structural- and chemical-order analyses discussed in the paper. The files are formatted as multi-column comma-separated values (CSV) files, which can be read by Microsoft Excel, OpenOffice and many other spreadsheet or data-analysis packages.

3. *-FinalConfiguration.vasp
The final structures obtained from the subsequences in the main depression and potentiation sequences discussed in the paper. These are in the VASP POSCAR format (http://cms.mpi.univie.ac.at/vasp/guide/node59.html, last checked 18/06/2015), and can be viewed using e.g. VESTA (http://jp-minerals.org/vesta/en/, last checked 18/06/2015).

4. *-FinalConfiguration-DOS.csv
The electronic density of states (DoS) curves computed for the final configurations obtained from the main depression and potentiation simulations discussed in the paper. This data is presented in Fig. 4. As for #2, the files are in the CSV format. Each contains three columns - the first is the energy, referenced to the Fermi level, the second is the energy-dependent DoS, and the third is its cumulative integral.

5. *-FinalConfiguration-DielectricTensor.csv
The real and imaginary dielectric tensors computed for the final configurations obtained from the main depression and potentiation simulations discussed in the paper. The reflectance spectra presented in Fig. 4 can be derived, along with other properties, from the dielectric functions. As for #3, the files are in the CSV format. Each contains seven columns - the first is the energy, and the remainder are the independent components of the tensors, viz. x, y, z, xy, yz and xz.