Dear MS Users,

I am using Forcite for MD simulations of an organic compound using the COMPASSIII force field. It seems that there is a bug for the forcefield parameter n2= (nitrogen, two bonds). Every time a nitrogen is present with this forcefield parameter, the MD simulations become unstable at some point and result in an error message "An unphysical integration step (>100 Angstroms) has been detected". Reducing the time step to 0.1 fs or optimising the structure does not help.

Has anyone had a similar problem?

Best Wishes

Marek Sierka