2.1 KiB
lj_monte_carlo
Simple Lennard Jones Liquid MC simulation implemented in Rust
To compile, run:
// release builds are much faster because of enabled lto
cargo build --release
The compiled binary can then be found in target/release.
Phase diagram of a 6-12 lj fluid
(cutoff rc of 3.5 sigma)
Source: Ge J. et ak., Scaling behavior for a pressure and energy of shearing fluids. Phys Rev 061201, p. 67-68, 2003
Results
Some results obtained during the creation of this project
Function of State
Function of state at different temperatures. 512 particles were simulated with applied potential shift and tailcorrection. Displacement scaled to have 33% acceptance rate during 1mio steps. Averages over 100k steps.
Energy minimization for a box of 2048 particles at T=0.9 and Density=0.7
Coexisting liquid/vapor phases
2048 particles were inserted into a box at T=1.0 and density=0.85 (Dimensions 13.406/13.406/40.218), no tailcorrection, cutoff 2.5. The particles filled 1/3 of the box with vacuum space above and below the liquid slab. Finally, a simulation was run for 50000+5000 Cycles (each 2048 steps) writing a frame every cycle.
Density profile avg. over the last 5000 cycles.
Chemical potential over all 55000 cycles. z=11.07 and z=27.57 were chosen as liquid boundaries. For every frame, 100 particles insertions per phase were performed.
Surface tension: Running average over the last 5000 Cycles.
P_zz: -0.05981
P_xy: -0.06715
Tension: 0.14756
TODO shift virial
TODO Large sampling is required here. Tension has lots of ups and downs over the 5000 steps (.1 to .25). Increase number of steps to get a better average.