BN nanoribbon simulation convergence issues

[yasar]

Hello
I'm trying to simulate zigzag BN nanoribbon as attached. However the simulation does not converge beyond 0.6V of bias voltage even if I increase iteration steps to 300. Could you please help me hpw to address this issue? I tried ATK 13.8 and 2014.0 but both didn't converge

Note: I got the simulation parameters and the geometry from this paper which claims to have used ATK: "Chlorine sensing properties of zigzag boron nitride nanoribbons" http://www.sciencedirect.com/science/article/pii/S0038109814000222

Best regards,
Yasar

[Anders Blom]

Why only one side is H-terminated? Also, the central region is probably too short for high bias.

[yasar]

Thanks. Will try these recommendations.