thanks for your reply.I wrote the heat/flux command in input script but in this formula I don’t know how calculate the interactions among of one type of atom.the pe/atom and stress/atom command give us the total interaction of two type of atoms.
can I write it yet ?
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Good news. This formula represents a partition of the global enthalpy KE+PE+p*V into alpha and beta components of a binary mixture. The partition is based on a finer partition over atoms, and this is the same as what LAMMPS uses for per-atom energy and per-atom stress. In all cases, summing up the atom components recovers the global energy and virial. So, you can get your enthalpy for components alpha and beta by first computing per-atom ke, pe, and stress, and then summing each of these for atoms of the same type to get ke_alpja, pe_alpha, and stress_alpha, and then, if you want, adding these togther to get h_alpha.
See:
http://lammps.sandia.gov/doc/compute_ke_atom.html
http://lammps.sandia.gov/doc/compute_pe_atom.html
http://lammps.sandia.gov/doc/compute_stress_atom.html
http://lammps.sandia.gov/doc/compute_reduce.html
Also, as a sanity check, you should be able to add the alpha and beta components together to match the global enthalpy computed by thermo custom:
http://lammps.sandia.gov/doc/thermo_style.html
When computing thermo quantities, you always need to be careful about:
-Sampling effects
-Contributions due to center-of-mass motion
-Reference states
Aidan