[gmx-users] Logfile incorrectly (?) has dVbonded/dl terms

[Dries Van Rompaey]

Hi gmx-users,

I'm currently using FEP introduce a small change in my molecule. As a first
step, I'm simply removing the coulomb interactions for the part that's
being transformed into dummies. No other interactions are being modified.

However, in my logfile I find:
Bond          Angle    Proper Dih.  Improper Dih.          LJ-14
9.44315e+01    1.50317e+02    1.02598e+02    5.65505e+00    7.01417e+01
Coulomb-14        LJ (SR)  Disper. corr.   Coulomb (SR)   Coul. recip.
-2.09477e+03    1.55917e+04   -5.21597e+02   -1.17294e+05    9.63595e+02
Potential    Kinetic En.   Total Energy    Temperature Pres. DC (bar)
-1.02932e+05    1.92182e+04   -8.37142e+04    2.99969e+02   -1.11454e+02
Pressure (bar)       dEkin/dl      dVcoul/dl       dVvdw/dl    dVbonded/dl
8.26672e-01    0.00000e+00   -4.21612e+01    0.00000e+00    1.50215e+01
dVrestraint/dl
0.00000e+00

My lambda vectors are:
mass_lambdas             = 0.00 0.00 0.00 0.00
coul_lambdas             = 0.00 0.25 0.75 1.00
vdw_lambdas              = 0.00 0.00 0.00 0.00
bonded_lambdas           = 0.00 0.00 0.00 0.00
restraint_lambdas        = 0.00 0.00 0.00 0.00
temperature_lambdas      = 0.00 0.00 0.00 0.00


I'm a bit confused by the dVbonded/dl in the logfile. Seeing as I'm not
doing anything to my bonded interactions, shouldn't that be zero?

Thanks,

Dries