[gpaw-users] (no subject)

[mohamed amin]

Hi Ask,
I have tried to send my questions to the GPAW list many times but I never see them posted although I'm getting the messages from other users.
I wanted to know why when I start td propagation the energy is very different that the ground state energy. For example, when I ran the same calculations on octopus, the td calculations start with the ground state energy then it changes gradually with time. In GPAW, the td energies are positive while the gs are negative. I don't know what is the source of error.
Here is my gs input:
jellium.calc = GPAW( poissonsolver=poissonsolver, # use special Poisson solver
                     xc='LDA',
                     charge=-nelec,          # charge of electrons, total charge = Z - nelec
                     nbands=nstates,
                     h=.50,
                     txt='Na.txt',
                     eigensolver='cg',                #'rmm-diis','cg'
                     occupations=FermiDirac(width=0.05),
                     mixer=mixer,
                     convergence=convergence,
                     maxiter=2000)

jellium.calc.attach(jellium.calc.write, 10, 'rest.gpw')
# find electronic states
e0 = jellium.get_potential_energy()

# save states
jellium.calc.write('na.gpw', mode='all')

and my td input

time_step = 1.0 # 8.0 as (1 as = 0.041341 autime)5D
iters =  4000     # 2000 x 8 as => 16 fs
# Weak delta kick to z-direction
kick = [0,0,5e-3]
print "*********************************Starting TDDFT calculations******************************"
# TDDFT calculator
td_calc = TDDFT('na.gpw')
# Kick
td_calc.absorption_kick(kick)

frequencies = [2.80, 2.98]     # Frequencies of interest in eV
folding = 'Gauss'             # Folding function
width = 0.1                   # Line width for folding in eV
ind = TDDFTInducedField(paw=td_calc,
                        frequencies=frequencies,
                        folding=folding,
                        width=width,
                        restart_file='331_jellium_td.ind')


# Propagate
td_calc.propagate(time_step, iters, '331_jell.dat', '331_JELLIUM_td.gpw')
td_calc.write('331_JELLIUM_td.gpw', mode='all')
ind.write('331_jellium_td.ind')
photoabsorption_spectrum('331_jell.dat', '331_spectrum_z.dat')

Thanks

Sincerely,

Muhamed Amin