[gmx-users] the segmentation fault for MD with constraints=none!

[David van der Spoel]

Rongliang Wu wrote:
> dear all,
> thanks for your great suggestions and i have met with new problems in
> simulation of bulk systems or crystal cells when no constraints are
> utilized, the systems either explode or met with "segmentation fault"!
> and i am sure my systems are well minimized.
> and again when constraints= all-angles, the system often collapse.
> i have always being using the all-bonds constraints, but the bond length
> distribution can no be thus derived.
> the constraint parameters in mdp files are defaults!
> best regards!
> 
>
Please state clearly
+ objective
+ what you have tried
+ if there were problems

If I read you correctly you want to study bond length distributions, in
which case you need to turn off constraints and reduce the timestep to
between
0.2 and 0.5 fs.


-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Assoc. Prof., Molecular Biophysics group,
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://folding.bmc.uu.se
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