PIMMS: Polymer Interactions in Multi-component MixtureS
PIMMS is a lattice-based, coarse-grained Monte Carlo simulation engine for exploring the phase behaviour and conformational properties of polymer systems - single homo- or hetero-polymers, many-chain mixtures, and biomolecular condensates - in both 2D and 3D.
Highlights
Easy to use. Installation provides a command-line executable (
PIMMS) that runs a simulation directly from a plain-text keyfile.Fast. The hot loops are written in optimised Cython that compiles to native C, with an optional multi-threaded (OpenMP) kernel.
Flexible interactions. Drive interactions over three distinct length scales (short / long / super-long range) plus solvation and backbone-angle terms, all defined in a simple parameter file.
Many components. Simulate arbitrary mixtures of distinct polymer species to study co-assembly and phase separation.
Rich move set. Local and collective Monte Carlo moves - crankshaft, reptation (slither), cooperative pull, rigid-body cluster moves, virtual-move Monte Carlo (VMMC) and temperature-switch (TSMMC) moves - to sample efficiently and escape kinetic traps.
If you are new to PIMMS, start with Installation and then work through the Overview.
User Guide
- Installation
- Overview
- Input files
- Restart files
- Output files
- Keyword reference
- Core simulation setup (most are required)
- System & chain options
- Monte Carlo moves (the MOVE_* probabilities must sum to 1.0)
- Move tuning
- TSMMC (temperature-switch) excursion settings
- Quench / simulated annealing
- Output & I/O
- Analysis
- Restart
- Equilibration options
- Parallelization
- Experimental features
Moves
Advanced Features
Analysis (lemonade)
Development