HvD: A special version of autoxc to deal with a class of correlation meta-GGAs that are clumpsilly defined so as to generate numerically unstable expressions for the partial derivatives. Hence as tau goes to zero we need to impose special conditions to ensure that the LDA is recovered. The functionals in question include the VS98, M05, M06, PKZB and TPSS correlation functionals. Truhlar and co. fixed this problem in their M08 functional, and Becke in his 1995 functional avoided the particular unstable factor.  This is a first version of this special script. It is not tested yet, but I  just wanted to secure it right now.
HvD: A special version of autoxc to deal with a class of correlation meta-GGAs
that are clumpsilly defined so as to generate numerically unstable expressions
for the partial derivatives. Hence as tau goes to zero we need to impose
special conditions to ensure that the LDA is recovered. The functionals in
question include the VS98, M05, M06, PKZB and TPSS correlation functionals.
Truhlar and co. fixed this problem in their M08 functional, and Becke in his
1995 functional avoided the particular unstable factor. 
This is a first version of this special script. It is not tested yet, but I 
just wanted to secure it right now.





rangsimanketkaew/NWChem