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[silvia@cii.fc.ul.pt]

Dear ABINIT users,

I'm trying to optimize one phenol molecule using the Perdew-Burke-Ernzerhof 
GGA functional (ixc=11) and Fritz-Haber-Institute (FHI) pseudopotentials 
within the GGA aproximation.
I'm considering a unit cell with dimensions 20.0 20.0 20.0. I'm using the 
data set mode to vary the value of ecut while maintaining the cell dimensions 
fixed. The problem is that I'm not getting convergence on the force gradients 
during the Broyden minimization (ionmov=3). I've used 35.0 and 40.0 hartree 
as ecut values and 100 optimization steps (ntime=100). I'm not achieving 
convergence on the SCF cycles either.

This is the input file I'm using:

ndtset 4
acell 20.0 20.0 20.0
ecut: 35.0 ecut+ 5

ntypat 3            
znucl 8 6 1         

natom 13
typat 1 1 1 1 1 1 2 2 2 2 2 3 2   

xangst

            0.939974   -0.024981    0.000001
            0.221909   -1.222557    0.000001
           -1.169193   -1.188258    0.000000
           -1.854307    0.027925   -0.000001
           -1.128953    1.217603    0.000000
            0.265046    1.197679    0.000000
            0.767230   -2.166033    0.000004
           -1.725398   -2.126674    0.000001
           -2.943885    0.047328    0.000000
           -1.649437    2.176230   -0.000001
            0.828963    2.133524   -0.000001
            2.300265   -0.110628   -0.000003
            2.673550    0.776176    0.000014

ixc  11

nkpt 1
ntime 100
ionmov 3
tolmxf 5.0d-5

iscf 3            # Algorithm for SCF
nstep 50          # Maximal number of SCF cycles
toldff 5.0d-6
diemac 1.0        
diemix 0.5        

                 
Can someone give me some clue on what I'm doing wrong or not doing at all? 
Any help would be greatly appreciated...

Best regards,
Sílvia Estácio