[Pw_forum] something about Pt.pw91-n-van.UPF

[Agostino Migliore]

Hello

Until the smearing is not fully negligible (so that you still have
appreciable fractional occupations) also E=F-(-TS)=(E-TS)-(-TS) (that is
the difference between the two quantities directly provided by the code)
will be a function of the spreading paramater. On the other hand, if you
get the energy with a small enough smearing, a good estimate for the
energy without smearing is given by the equation

[F(T)+E(T)]/2=E(0)+O(T^n), with n>2,

which you can find in
O. Grotheer and M. Fa¨hnle, PRB (1998), 58, 13459.

Best,
Agostino Migliore
CMM, Chemistry Department, UPenn
Philadelphia, PA