[gmx-users] 1-4 table size of 0 nm

Adrien Leygue adrien.leygue at gmail.com
Fri Oct 19 13:47:27 CEST 2007

Dear Gromacs users,

I am using Gromacs with a fully tabulated potentials.

I have created the table_X_Y.xvg  and tablep_X_Y.xvg files (which are
identical in my case) but when I run gromacs to perform an initial
energy minimization I get the following error message:

Warning: 1-4 interaction between 6 and 1 at distance 0.589 which is
larger than the 1-4 table size 0.000 nm
These are ignored for the rest of the simulation

This interaction between atoms 6 and 1 is a standard 1-4 interaction
and is the first one in the  pairs section. To get rid of the problem,
I have to remove the whole pairs section.

The 0 nm part is really strange to me, as if Gromacs is not generating
the tables for the 1-4 or doesn't recognizes the provided files.

I am using Gromacs 3.3.2 in double precision, I have modified the
source code of 2 routines:

-xtcio.c as suggested in a previous post to correct a bug that was
present when running in double precision & parallel

-I increased the value of MAXPTR in src/kernel/readir.c as suggested
by B. Hess in a previous post as I have many table_X_Y.xvg files (I
still have less than 254 groups, so having the group number as a uchar
is not a problem).

I welcome any suggestion/hint for solving the problem.


Adrien Leygue

Department of Materials Science and Engineering
School of Chemical Engineering
National Technical University of Athens
9 Heroon Polytechniou Street
Zografou Campus, Athens 157 80,
Tel/Fax: +30210 772-3112

More information about the gromacs.org_gmx-users mailing list