Why can't device from bulk be implemented along the c direction?

[dong0216]

When building devices，device from bulk can be realized before optimization(graphdiyne-V2C.py). Why can't device from bulk be realized along the transportation direction after optimization(graphdiyne-V2C-opt.py)? I hope to get your reply. Thanks.

[Petr Khomyakov]

The easiest way of doing device optimization is to use Optimize Device Configuration study object, see https://docs.quantumwise.com/tutorials/optimize_device_configuration/optimize_device_configuration.html and https://docs.quantumwise.com/webinars/webinars.html#relaxation-of-electronic-devices-and-interfaces.

If you have a QuantumATK version older than 2018, then you may do the device optimization as described in https://docs.quantumwise.com/tutorials/device_relaxation/device_relaxation.html.

My guess is that in your bulk configuration calculation you did optimize that part of the system that is supposed to be electrode extensions when building Device from Bulk. That part should be Fixed or Rigid while doing optimization. The study object does it automatically. Otherwise, one should impose the corresponding constraints manually. 

[dong0216]

Thanks for your reply. I will try again.