LAMMPS GJ THERMOSTAT EXAMPLE Required LAMMPS packages: EXTRA-FIX, MOLECULE, EXTRA-PAIR This directory contains the ingredients to run an NVT simulation using the GJ thermostats. Example: NP=4 #number of processors mpirun -np $NP lmp_mpi -in.gjf.vhalf Compared to other thermostats, the GJ thermostat allows for larger timesteps with the correct Boltzmann statistics. A comparison using averaged properties from this example's input file is shown below. 'X' denotes a failed simulation. The theoretical value for KE is 1.1168 eV. POTENTIAL ENERGY (eV) | Δt || 0.01 | 0.05 | 0.10 | 0.11 | 0.12 | 0.13 | 0.14 | |===================||========|========|========|========|========|========|========| | gjf half || -55.11 | -55.11 | -55.11 | -55.11 | -55.11 | -55.10 | -55.07 | | gjf full || -55.11 | -55.11 | -55.11 | -55.11 | -55.11 | -55.10 | -55.07 | | langevin || -55.11 | -55.07 | -54.87 | -54.79 | -54.65 | X | X | | nvt (Nose-Hoover) || -55.14 | -55.07 | -54.90 | -54.84 | -54.76 | X | X | |-------------------||--------|--------|--------|--------|--------|--------|--------| KINETIC ENERGY (eV) | Δt || 0.01 | 0.05 | 0.10 | 0.11 | 0.12 | 0.13 | 0.14 | |===================||========|========|========|========|========|========|========| | gjf half || 1.117 | 1.116 | 1.119 | 1.119 | 1.123 | 1.136 | 1.170 | | gjf full || 1.116 | 1.071 | 0.938 | 0.898 | 0.858 | 0.817 | 0.780 | | langevin || 1.110 | 1.113 | 1.121 | 1.129 | 1.157 | X | X | | nvt (Nose-Hoover) || 1.083 | 1.109 | 1.112 | 1.113 | 1.114 | X | X | |-------------------||--------|--------|--------|--------|--------|--------|--------| Script Commands: -- fix lang all gjf 10 10 1 26488 -- fix lang all gjf 10 10 1 26488 vel vfull -- fix nve all nve fix lang all langevin 10 10 1 26488 -- fix noho all nvt temp 10 10 1 --