Interlayer distance in Bilayer graphene

[mano]

In quantumwise website tutorial, the experimental value of interlayer distance in bilayer graphene is given as 3.32 Ang (http://quantumwise.com/documents/tutorials/latest/Grimme/index.html/chap.graphene.html). When I checked the reference  "N. N. Greenwood and A. Earnshaw, Chemistry of the elements, Pergamon, (New York), 1998." (this is updated version of 1984), I found it is 3.35 Ang. Another reference "Delhaes, P. (2001). Graphite and Precursors. CRC Press. ISBN 90-5699-228-7", also mentioned the interlayer distance is 3.35 Ang. My question is, whether I have made wrong in checking those reference or 3.32 Ang is the correct value?

[Anders Blom]

A distance (difference) of 0.03 Å is pretty difficult to resolve in an experiment, and certainly in a calculation too. I doubt the difference between 3.32 and 3.35 is significant, but rather just different methods give (slightly) different results. It may be temperature-dependent, environment-dependent, etc.

[mano]

Dear Dr. Anders Blom,
          Thank you for your immediate reply.

With regards,
Manoharan M.