FUNCTIONAL NAME: NAX-E1
This is a KINETIC ENERGY Density Functional Theory functional
FUNCTIONAL FAMILY: LDA
DESCRIPTION: Perdew & Wang (modified)
REFERENCES
J. P. Perdew and Y. Wang., Phys. Rev. B 45, 13244 (1992)
DOI: 10.1103/PhysRevB.45.13244
Added extra digits to some constants as in the PBE routine (http://dft.rutgers.edu/pubs/PBE.asc).