Upper limit of Miller indices of BCC and FCC crystals?

[wangasu]

does anybody know the upper limit of the bcc and fcc metals like Fe, Cu, Ag? According to the fact that the planes with high (hkl) indices have small interplanar spacing d_hkl, the smallest spacing would be present. what is that? atomic diameter of a specifc metal?

 

[M Quack]

I don't think that there really is an upper limit, but you are right that larger and larger reciprocal space vectors correspond to smaller and smaller real space distances, and at some point that becomes meaningless. As far as I can tell, in practice nobody is ever bothered by this.

The smallest meaningful reciprocal distance would be 2pi/(crystal size). That is something experimentally relevant, for example in nanomaterials.