DOI: 10.5281/zenodo.13167614
title: Molecular Dynamics Simulations of PEO-LiTFSI Polymer Electrolytes With Various Chain Lengths Confined Between Charged Electrodes With Various Surface Charges

description: Data set containing molecular dynamics (MD) simulations performed with Gromacs to investigate the effect of polymer chain length and electrode surface charge on the atomistic structure and dynamics of PEO-LiTFSI polymer electrolytes in the vicinity of charged, graphite-like model electrodes. The model electrodes carry a surface charge of +/- 0.25 e/nm², +/- 0.50 e/nm² and +/- 0.75 e/nm². Data for surface charges of +/- 0.00 e/nm² and +/- 1.00 e/nm² are contained in https://doi.org/10.5281/zenodo.13164944 and https://doi.org/10.5281/zenodo.13166152, respectively.

PEO = Methoxy-terminated poly(ethylene oxide), sometimes also abbreviated as PEGDME for polyethylene glycol dimethyl etherLiTFSI = Lithium bis(trifluoromethanesulfonyl)imide, sometimes also abbreviated as Li[NTf2].

The data set contains:



Gromacs input and output files (except trajectories due to their huge filesize)

Processed data
description: General file naming scheme: <settings>_[out]_<system>.ext



General <settings> scheme: <step>_<ensemble><temperature>_<barostat>_<thermostat>



<step>: Acronym for the current simulation step



em = energy minimization

eq = equilibration run

pr = production run



<ensemble>: Simulated thermodynamic ensemble



npt = Isothermal-isobaric ensemble

nvt = Canonical ensemble



<temperature>: Simulated temperature in Kelvin

<barostat>: Acronym for the used barostat



be = Berendsen barostat

pr = Parrinello-Rahman barostat



<thermostat>: Acronym for the used thermostat



ld = Langevin dynamics

be = Berendsen thermostat

vr = Velocity rescale thermostat

nh = Nosé-Hoover thermostat








_out_: For Gromacs output files




General <system> scheme: <salt>_<solvent>_<EO-Li ratio>_<electrode>_q<q>_<charge scaling>



<salt>: Acronym for the used conducting salt



lintf2 = Lithium bis(trifluoromethanesulfonyl)imide



<solvent>: Acronym for the used solvent



g<n> = Glyme with n monomers (i.e. n + 1 ether oxygens) per chain

peo<n> = Methoxy-terminated poly(ethylene oxide) with n monomers (i.e. n + 1 ether oxygens) per chain



<EO-Li ratio>: Salt concentration measured as the ratio of ether oxygens to lithium ions

<electrode>: Used electrode



wall = Implicit wall/electrode (no periodic boundary conditions in z dimension)

gra = Graphite-like model electrode (fixed Lennard-Jones particles)



q<q> = Electrode surface charge in e/nm²

<charge scaling>: Charge scaling factor for ionic species. In all simulations, the atomic point charges of ionic species were reduced by 80 %.




Note that most of the files are compressed with gzip (recognizable by an additional .gz extension). To decompress gzipped files on Linux systems run gzip --decompress filename.ext.gz.

 

General directory structure:

+--system_1/
|  +--equilibration_run_1/
|  |  +--input_files.ext
|  |  +--output_files.ext
|  |
|  +--equilibration_run_2/
|  |  +--...
:  :
|  +--production_run/
|     +--input_files.ext
|     +--output_files.ext
|     +--analyses/
|        +--gmx/  # Analyses performed with Gromacs tools
|        |  +--rdf/
|        |  +--...
|        |   
|        +--mdt/  # Analyses performed with MDTools (https://zenodo.org/doi/10.5281/zenodo.7615177)
|        |  +--msd/
|        |  +--...
|        |
|        +--vmd/  # Analyses performed with VMD (https://doi.org/10.1016/0263-7855(96)00018-5)
|           +--snapshots/
|           +--...
|
+--system_2/
|  +--...
: