AMBER Archive (2009)

Subject: [AMBER] SANDER BOMB

From: PRADEEP VENKATARAMAN (pvtulane_at_gmail.com)
Date: Wed May 27 2009 - 21:39:56 CDT

Hi All,

I am trying to do a NPT simulation on 300 methane molecules in 25 X 25 X 25
box at 1 atm and 300 K.

So initial density is 0.768 g/cc which is closer to actual density of
methane gas.

Since there is no solvent, the volume is expected to increase very rapidly.
Hence I use taup=20.0 and dt =0.002.

But despite using such a high value pressure relaxation time, I encounter
the following error.

==============================================================================

 NSTEP = 72500 TIME(PS) = 245.000 TEMP(K) = 299.82 PRESS =
682.2
 Etot = 1192.0434 EKtot = 982.1689 EPtot =
209.8745
 BOND = 0.0000 ANGLE = 515.3580 DIHED =
0.0000
 1-4 NB = 0.0000 1-4 EEL = 0.0000 VDWAALS =
-305.4415
 EELEC = -0.0420 EHBOND = 0.0000 RESTRAINT =
0.0000
 EKCMT = 260.7883 VIRIAL = -135.4252 VOLUME =
26899.9942
                                                    Density =
0.2971
 Ewald error estimate: 0.7127E+00
 ------------------------------------------------------------------------------

check COM velocity, temp: 0.009243 0.06(Removed)
SANDER BOMB in subroutine nonbond_list
volume of ucell too big, too many subcells
list grid memory needs to be reallocated, restart sander

=============================================================================

Please help me understand the cause of this problem.

Thanks,

Pradeep
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