Mohammad, First, you don't need mpirun to run gnubands. The program only takes a few moments to run, even with very large systems and there is no parallelization implemented. It just reshapes the band structure arrays into something more easily plotted. Just use:
$ gnubands < QD.bands > QD_bands.dat Second, if you navigate to the directory where gnubands.f lies and open gnubands.f with your favorite file editor, you will see that there are some maximum limits that can halt the program. (the line -> if(overflow) stop...) Adjusting, for example, maxb upwards to a higher value (perhaps a MUCH higher value) where it is originally declared as 100, then recompiling gnubands, will fix your issue with the program. Likewise, if you continue to obtain the same error, perhaps you have breached the maxk limit for the number of k-points in your plot. Friendly regards, -- *Abraham Hmiel* Katherine Belz Groves Fellow in Nanoscience Xue Group, College of Nanoscale Science and Engineering at SUNY Albany http://abehmiel.net/about
