enthalpy

Dear lammps users
In the manual, compute heat/flux command show us that heat current vector was culated as:

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but in the origin paper:
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33.jpg
h is the enthalpy per particle,why lammps ignore this term? if I want to compute this term,can lammps achieve it ? and how to add it into the G-K in lammps?
Thanks!
Jack zhuang

what is the enthalpy for a system with constant volume?

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11.jpg

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