[myth_buster]

I think it would have been useful to have the graph reflect discipline's color.

[adw]

The Perdew-Burke-Enzerhof functional, and the generalized gradient approximation, is a Big Honking Deal for accurate quantum-mechanical simulation of solids.

For more: http://en.wikipedia.org/wiki/Density_functional_theory

(I used to be a happy customer, back when I was a scientist.)