[gmx-users] Conserved energy decreases linearly

[David van der Spoel]

Hi,

I'm doing NVT simulations of pure liquids with a Nose-Hoover thermostat and
    ref-t:      298.15
    tau-t:         0.2
    cutoff-scheme        = Group
    ns_type              = Grid
    nstlist              = 5
    coulombtype          = PME
    coulomb-modifier     = None
    rcoulomb-switch      = 0
    rcoulomb             = 1.1
    vdwtype              = Cut-off
    vdw-modifier         = None
    rvdw-switch          = 0
    rvdw                 = 1.1

the conserved energy drops by 8 kJ/mol/ns (0.23 kJ/mol/ns/dof).
No constraints are used.

Is this normal or too large a drop in conserved energy?

Any tips to update the protocol?
-- 
David van der Spoel, Ph.D., Professor of Biology
Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205.
spoel at xray.bmc.uu.se    http://folding.bmc.uu.se