[gpaw-users] (no subject)

[Ask Hjorth Larsen]

Hello Amin

2016-03-31 18:42 GMT+02:00 mohamed amin <siasas at yahoo.com>:
> 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.

I guess this will reach the mailing list now then.  Unfortunately I am
not so well into the time-dependent code.  Maybe someone else can have
a look?

Note: I recommend attaching entire scripts rather than inline snippets.

Also, who can tell why Amin's e-mails might not be arriving to the mailing list?

Best regards
Ask

> 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