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dCCI method

dynamic Clausius–Clapeyron integration (dCCI)

dCCI方法的优点在于，它使用相对较短的单次非平衡模拟，提供了跨越大范围热力学状态的共存曲线

安装配置环境

Clone DCCI库到src文件

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cd ./lammps-23Jun2022/src/
git clone https://github.com/samuelcajahuaringa/dCCIforLAMMPS.git DCCI

Copy文件

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cd ./DCCI
cp fix.h fix_nh.* fix_adapt_dcci.* dcci.cpp dcci.h ../

如何理解：the pair style modified to scale the forces such as pair lj. 需要做什么修改？

不做修改，make mpi未报错。

构建dcci和编译lammps

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cd ..
make yes-DCCI
make mpi -j8

成功编译

LAMMPS版本：23Jun2022

测试环境：WSL Ubuntu20.04

Lennard-Jones固-液相边界例子

运行测试

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cd lammps-23Jun2022/src/DCCI/example/lj
mpirun -np 2 ~/softwares/Lammps/lammps-23Jun2022/src/lmp_mpi -partition 2x1 -in in.dcci

报错调试

• 2个处理器以上报错：ERROR: Processor partitions do not match number of allocated processors (../lammps.cpp:449)

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  ERROR: Processor partitions do not match number of allocated processors (../lammps.cpp:449) -------------------------------------------------------------------------- Primary job terminated normally, but 1 process returned a non-zero exit code. Per user-direction, the job has been aborted. -------------------------------------------------------------------------- -------------------------------------------------------------------------- mpirun detected that one or more processes exited with non-zero status, thus causing the job to be terminated. The first process to do so was: Process name: [[25094,1],1] Exit code: 1

• 默认两个处理器跑也报错：

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  LAMMPS (23 Jun 2022) Running on 2 partitions of processors -------------------------------------------------------------------------- MPI_ABORT was invoked on rank 1 in communicator MPI_COMM_WORLD with errorcode 1. NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes. You may or may not see output from other processes, depending on exactly when Open MPI kills them.

• 发现报错处理器数无关

  • -partition 2x1 参数表示采用两个处理器分区，每个处理器分区中都运行一个 MPI 进程

  • 如果增加总进程为8，则需要修改为：-partition 2x4

    采用两个处理器分区，每个处理器分区中都运行4个 MPI 进程

• 查看log文件发现还是报错：

  1 2	ERROR: Thermo fix does not compute scalar (../thermo.cpp:1019) Last command: thermo_style custom step temp ke pe etotal press vol f_f3

  f3是一个标量？

  注释 f_f3后不报错了

结果分析

• 结果在log.lammps中；
• 对比分析：
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参考

[1] Cajahuaringa S, Antonelli A. Non-equilibrium free-energy calculation of phase-boundaries using LAMMPS[J]. Computational Materials Science, 2022, 207: 111275.

[2] dCCIforLAMMPS: Examples demonstrating how to reproduce the results in the paper [1].