Dear all, I've found a bit strange behavior of cppp.x tool while dealing with vc-cp dynamics of 167-atomic supercell of silicon nitride. I perfomed the 500 steps of variable-cell Car-Parrinello molecular dynamics and then ran it through cppp.x to have an AXSF-file as output. After opening the animation in the XCRYSDEN I can see, that during some number of steps atoms are moving properly from their initial positions (which were achieved after ionic relaxation). But then at some certain time step atoms revert to their original positions specified in the input file for cp.x. After that atoms are starting to move continuously again, but after some steps the leap is reapeted. It's obvious that such movement does not correspond to real behavior of the system, at least because in the cp.x output file there are no leaps in atomic positions (I've checked it by putting 'iprint = 1'). Any help is greatly appreciated.
Best regards, Nekrashevich Sergey.
