This is the simulation data set for the manuscript: Arvelo DM, Comer J, Schmit J, Garcia R (2024) Interfacial water is separated from a hydrophobic silica surface by a gap of 1.2 nm. ACS Nano 18:18683–18692. https://doi.org/10.1021/acsnano.4c05689 This data set includes all files needed to run and analyze the simulations described in the this manuscript in the molecular dynamics software NAMD, as well as the output of the simulations. LAMMPS input files for the ReaxFF simulations are also included. The files are organized into directories corresponding to the figures of the main text and supporting information. They include molecular model structure files (NAMD psf or LAMMPS data), force field parameter files (in CHARMM format or ReaxFF format), initial atomic coordinates (pdb format), NAMD or LAMMPS configuration files, Colvars configuration files, NAMD or LAMMPS log files, and output including restart files (in binary NAMD format) and trajectories in dcd format (downsampled with a stride of 100 to 20 ns per frame). Analysis is controlled by shell scripts (Bash-compatible) that call VMD Tcl scripts or python scripts. These scripts and their output are also included. Version: 1.0. Figure5AC: Simulation of pentadecane on a 5 chains/nm^2 OTS layer. Figure5B_FigureS7: Calculation of force profile for an SiO2 tip asperity model using adaptive biasing force. Systems: octane with 5 chains/nm^2 OTS, octane with 4 chains/nm^2 OTS, decane with 5 chains/nm^2 OTS, water with 5 chains/nm^2 OTS. FigureS6: Simulations showing the effect of octadecane on the structure of the OTS layer for 3 and 5 chains/nm^2 densities. FigureS8: Calculation of the adsorption free energy of tetracosane (C24) at the OTS–water interface using ABF. FigureS9: Python script for estimating the critical concentration to form an alkane layer at the OTS–water interface using the mean-field Ising model. FigureS10: ReaxFF simulation and modeling to create the silanol-terminated amorphous silica model of an AFM tip asperity. FigureS11: Molecular dynamics simulations showing spontaneous assembly of twelve or twenty-four tetracosane (C24) molecules at the interface between water and the alkyl groups of an OTS-conjugated silica surface.
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Type Label Framework for Bonded Force Fields in LAMMPS
New functionality is added to the LAMMPS molecular simulation package, which increases the versatility with which LAMMPS can interface with supporting software and manipulate information associated with bonded force fields. We introduce the “type label” framework that allows atom types and their higher-order interactions (bonds, angles, dihedrals, and impropers) to be represented in terms of the standard atom type strings of a bonded force field. Type labels increase the human readability of input files, enable bonded force fields to be supported by the OpenKIM repository, simplify the creation of reaction templates for the REACTER protocol, and increase compatibility with external visualization tools, such as VMD and OVITO. An introductory primer on the forms and use of bonded force fields is provided to motivate this new functionality and serve as an entry point for LAMMPS and OpenKIM users unfamiliar with bonded force fields. The type label framework has the potential to streamline modeling workflows that use LAMMPS by increasing the portability of software, files, and scripts for preprocessing, running, and postprocessing a molecular simulation.
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- PAR ID:
- 10549374
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- The Journal of Physical Chemistry B
- Volume:
- 128
- Issue:
- 13
- ISSN:
- 1520-6106
- Page Range / eLocation ID:
- 3282 to 3297
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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