[gpaw-users] (no subject)

[Rizwan Ahmed]

Dear GPAW-users,

Have any one used BondSpring (..........). It forces bond-lengths between atoms under the maximum bond-length (threshold length) by applying force. But it does not seem to work in my case. Do any one know what could be the possible problem?

slab = io.read('start.traj')

newoutfile = 'Pt111_323_2OH_2H2O_1H3O'

calc = GPAW(nbands=-40,
                    h=0.19,
                    kpts = (4,6,1),
                    xc='RPBE',
                    poissonsolver=PoissonSolver(),
                    txt= newoutfile+'.txt',
                    maxiter = 300,
                    width = 0.1)

slab.set_calculator(calc)

cons = FixAtoms(mask=[atom.tag > 2 for atom in slab])
c = BondSpring(a1=31, a2=32, threshhold_length=1.20, springconstant=5.)
d = BondSpring(a1=31, a2=33, threshhold_length=1.20, springconstant=5.)
e = BondSpring(a1=31, a2=24, threshhold_length=1.20, springconstant=5.)

slab.set_constraint([cons, d, e, c])

io.write('slab.traj', slab)

qn = QuasiNewton(slab, trajectory='initial.traj')
qn.run(fmax=0.05)

energy = slab.get_potential_energy()


Thanks and best wishes,
Rizwan