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