How to build the model of armchair GNRs (Graphene nanoribbons) in Materials Studio?

Hi,

I used "graphene.xsd" which is in the 3D model file to build only zigzag GNRs. However, I didn't build armchair GNRs with this 3D model. So how can I build armchair GNRs in Materials Studio?

The best.

Ahmet