How to optimize the geometry of a Silicon nanoribbon?

[jim12565]

Hi

I have formed a silicon nanoribbon with the bond length of 2.2A and buckling of 0.43A as given in various papers. However I don't know how to optimize this geometry, i.e. selecting the k-point sampling and setting the optimize geometry part, especially in which coordinates (x, y, z) to constrain the cell? I'd be glad if you help about this question please.

P.S. I have attached the silicon nanoribbon unit cell to this post.

Best regards
Jimmy

[Petr Khomyakov]

It is totally up to you how to constrain the geometry in this calculation.  See https://docs.quantumwise.com/tutorials/geometry_optimization/geometry_optimization.html for some guidelines on geometry optimization. Note that the computational settings are to be chosen to achieve convergence of the physical quantities of your interest, e.g., total energy.

[jim12565]

OK, thanks Petr.