[gmx-users] How to obtain bond energy of the part of the system ?

[=?koi8-r?Q?=22?=Alex=?koi8-r?Q?=22=20?=]

Hi Gromacs Community!
  Suppose I have a system of a single hexane molecule in water and I run molecular dynamics for it. How can I obtain, for example, bond energy  of this hexane molecule only (not the whole system bond energy) or, say, kinetic energy of this hexane molecule (if I use thermostat for the whole system). 
  Yes, we use energygrps tag in our input file but the appropriate edr file when processed with g_energy allows to get only coulomb and vdw interaction between the groups of our system. 
  Thanks in advance, Alex.