g energy

The g_energy program extracts information from .edr files and prints the output to an .xvg file for plotting and / or further analysis.

You will notice that three kinds of Lennard-Jones energies may be reported. When calculating the non-bonded energies, GROMACS can handle twin-range cutoffs, depending on the settings in the .mdp file (and see the manual), so LJ-SR ("short-range") is the LJ contribution inside the shortest cutoff, and LJ-LR ("long-range") is outside the shortest cutoff, but within the longest. LJ-14 is the pair interaction contribution.

Analogously, energy terms for Coulombic interactions are also present in various forms.  Coul-SR is the Coulombic potential within rcoulomb.  Coul-14 is the pair interaction contribution.  There is no such term as Coul-LR.  Long-range electrostatics are calculated by various methods (PME, Reaction Field, etc) and thus show up as different terms, such as Coul-recip in the case of PME, a term that cannot be decomposed, regardless of the energygrps specified in the .mdp file.