restarting from saved checkpoint

[sathyajit]

Hi,

I am doing a transmission spectrum calculation with 2 metal electrodes and a central region of semiconductor. I see that the checkpoint .nc file is saved only till the point where Left and Right electrodes are converged. Is there a way to save checkpoints in between the central region convergence ?

Regards
Sathyajit

[Jess Wellendorff]

Dear Sathysjit, In short: no, you can not make ATK save the converged electrodes to the nc file before converging the full device. If you look in your script, the "update()" function call is the one that instructs ATK to compute the ground state electronic structure of the device. This is followed by the "nlsave" call, which writes the converged ground state to nc file. So the full device calculation must converge before it is written to nc.

Code

device_configuration.setCalculator(calculator)
nlprint(device_configuration)
device_configuration.update()
nlsave('myfile.nc', device_configuration)

Regards, Jess

[Umberto Martinez]

These two links can also be helpful:

http://quantumwise.com/publications/tutorials/item/116-reusing-electrodes
http://quantumwise.com/publications/tutorials/item/502-restarting-stopped-calculations