On Mon, 2011-02-21 at 13:59 +0100, Cyrille Barreteau wrote: > Dear all > > I have noticed an usual behavior when doing non collinear calculation > with a GGA pseudopotential. > > During the iteration process there are some NaN appearing in the output > file (see below). The strange thing is that the code continues and > converges.. > > iteration # 1 ecut= 35.00 Ry beta=0.30 > Davidson diagonalization with overlap > ethr = 1.00E-02, avg # of iterations = 2.0 > NaN NaN NaN
This error has been already corrected in the cvs version a few months ago. Note however that GGA + noncollinear is less stable than the other parts of QE. HTH, Andrea > > This type of Pb is not present when using a LDA pseudo. > > Moreover I have tried to do a calculation of a collinear configuration > with or without the 'noncolin' option. In principle both should lead to > almost the same solution. This is not the case. There are some > differences which according to me are larger than just numerical > errors.. > > I guess there is some kind of Pb when performing non collinear > calculations with a GGA pseudo. > > thanks to give me a hint to solve this problem > > cyrille > -- Andrea Dal Corso Tel. 0039-040-3787428 SISSA, Via Bonomea 265 Fax. 0039-040-3787249 I-34136 Trieste (Italy) e-mail: dalcorso at sissa.it