GROMACS version:
GROMACS modification: No
Please help me to calculate cohesive energy density in gromacs simulation md calculation
This paper goes over procedure to calculate CED. In a nutshell, you can use following formula to get CED.
CED = \frac{-E_{inter} \rho}{N_m M_w}
E_{inter} = Intermolecular energy
\rho= density
N_m= Number of molecules
M_w= Molecular weight
Calculating E_{inter} is tricky, you need to decide based on your system.
Regards,
Masrul