[Pw_forum] band structure of bi layer graphene

[Elie Moujaes]

Dear all,

 

I am trying to obtain the band structure of graphene. to do that, I supposed that celldim(1) =4.608737, celldm(3)=4.53666 so that c is 4.53666 *a....The carbon atoms are chosen such that:

 

 

ATOMIC_POSITIONS crystal
 C 0.000000  0.000000  0.000000  1 1 1
 C 0.000000  0.000000  0.200000  1 1 1
 C 0.333333  -0.33333  0.000000  1 1 1
 C -0.333333  0.33333   0.200000  1 1 1 
 

 

we have 4 carbon atoms in bilayer graphene and the primitive cell has a z direction of 0.2*c= 1/5 so that the primitive cell is 3D. Since QE is a 3D program, I thought that setting c= 4.5366 will produce an image of the primitive cell that is 4.53666*4.608737 Bohrs away from the original one so that no interaction happens( in the acse of which I will be modelling something similar to graphite). I got the results whioch are satisfactory but still need some  amendments...I just want to know if this line of thought is correct and if someone can have a look at the graph because it is not entirely correct. Maybe I need to increase the number of points.. I am open to suggestions if any...You will find ps file attached....

 

 

Regards

 

ELie moujaes

University of Nottingham

NG7 2RD

UK 
 		 	   		  
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