slab

[sara]

Dear friends,
I am trying to construct  tio2 rutile 110 slab.  which of these parts should I choose to create slab?

     non periodic and normal (slab)
     periodic and normal(electrode)
     periodic(bulk - like)
I have another question. Is  slab and layer the same?

[Umberto Martinez]

slab!
and add a vacuum region on above and below your structure.
The Surface Cleave plugin is used to create slabs here http://quantumwise.com/publications/tutorials/mini-tutorials/245 and here http://quantumwise.com/publications/tutorials/mini-tutorials/244
for example.

With "slab" you usually define the whole your structure which is formed by a certain number of layers.