Band structure for adsorbates on a slab
Posted: Mon Aug 11, 2008 3:49 am
Hi, I am studying interactions between molecular adsorbates on a slab. I placed the molecular adsorbates at various distances away from the slab and optimize the system, after which I calculated the band structures of the system according to the instructions in the manual. For a comparison, I calculate the band structure of the clean slab and the slab+adsorbate.
The band structure I obtained for the clean slab is reasonable.
For the slab+adsorbate, the bands of the adsorbate and the bands of the slab overlap. This overlap occurs even when the adsorbate molecule is very far away from the slab. (~7 angstroms) This is not making much sense to me. I thought that if the adsorbates are very far away, there shouldn't be much interaction with the slab?
Or the band structure calculated for the slab+adsorbate system are superpositions of the slab and adsorbate individually, and doesn't have any physical meaning?
The band structure I obtained for the clean slab is reasonable.
For the slab+adsorbate, the bands of the adsorbate and the bands of the slab overlap. This overlap occurs even when the adsorbate molecule is very far away from the slab. (~7 angstroms) This is not making much sense to me. I thought that if the adsorbates are very far away, there shouldn't be much interaction with the slab?
Or the band structure calculated for the slab+adsorbate system are superpositions of the slab and adsorbate individually, and doesn't have any physical meaning?