Giuliana Materzanini^1*, Tommaso Chiarotti^2*, Nicola Marzari^2*

1 Modelling Division, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium

2 Theory and Simulations of Materials (THEOS), École Polytechnique Fedérale de Lausanne, 1015 Lausanne, Switzerland and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fedérale de Lausanne, CH-1015 Lausanne, Switzerland

* Corresponding authors emails: giuliana.materzanini@uclouvain.be, tommaso.chiarotti@epfl.ch, nicola.marzari@gmail.com

DOI10.24435/materialscloud:nf-hr [version v1]

Publication date: Dec 09, 2022

How to cite this record

Giuliana Materzanini, Tommaso Chiarotti, Nicola Marzari, Solids that are also liquids: elastic tensors of superionic materials, Materials Cloud Archive 2022.170 (2022), doi: 10.24435/materialscloud:nf-hr.

Description

This work presents an application of the strain-fluctuation method, exploiting the fluctuations of the strain from extensive first-principles molecular dynamics simulations in the isobaric-isothermal ensemble, to the study of the elastic tensors of superionic materials. As the superionic materials for solid-state electrolyte applications usually do not have well-defined ground-state configurations, it is challenging to apply the static methods to calculate the elastic tensors of these materials. Instead, the strain-fluctuation method captures the dynamical nature of the elastic response of these materials and is a promising approach to studying their elastic properties. In this work: a protocol is presented and documented to extract the elastic the elastic moduli and their statistical errors from the molecular dynamics trajectories (open-source code available at https://github.com/materzanini); results for two benchmark superionic materials (Li₁₀GeP₂S₁₂ and Li₁₀GeP₂O₁₂) are given; for these superionic materials, a comparison to static methods is also provided, showing that static methods overestimate the moduli with respect to the correct dynamical treatment by ~25-50%.

Materials Cloud sections using this data

Files

File name	Size	Description
MD-SIMULATIONS.tar.gz MD5md5:e7e30c5e7bd615b8f38605e08f2b3325	104.4 MiB	Input and output files for the NPT-MD runs; the outputs of these runs (cell trajectories) serve as inputs for the strain-fluctuation method to extract the elastic tensors and moduli from the dynamics (open-source code at https://github.com/materzanini).
README_MD-SIMULATIONS.txt MD5md5:278999574fec929f1a653653817a6e03	710 Bytes	Detailed description of the contents of MD-SIMULATIONS.tar.gz.
STATIC-CALCULATIONS.tar.gz MD5md5:39d3819b216ec19d628f94650ce81a82	3.1 MiB	Input and output files for the static calculations (energy-volume isotropic compressions and Murnaghan fits; stress-strain calculations).
README_STATIC-CALCULATIONS.txt MD5md5:f1cbb091688b271d34bdd0bb8098858d	1.7 KiB	Detailed description of the contents of STATIC-CALCULATIONS.tar.gz.

License

Files and data are licensed under the terms of the following license: Creative Commons Attribution 4.0 International.
Metadata, except for email addresses, are licensed under the Creative Commons Attribution Share-Alike 4.0 International license.

External references

Keywords

elastic constants first-principles molecular dynamics statistical sampling stress-strain solid-state electrolytes LGPO LGPS MARVEL/Inc1 SNSF CSCS BIG-MAP superionics