If this flag is set to false
LSCALAPACK = .FALSE.scaLAPACK will not be used by VASP.4.2. This switch is required on the T3D/T3E if vasp was compiled with the scaLAPACK and several images are run at the same time by setting IMAGES=X in the INCAR file. If scaLAPACK is not switched of in the nudged elastic band mode on the T3D/T3E, vasp will crash.
MIND: in the Gamma point only version, the parallel sub space diagonalization (LscaLAPACK= True) is performed with a Jacobi algorithm instead of scaLAPACK. This routine was written by Ian Bush. The Jacobi routine is faster than scaLAPACK.