= Change the amount of HF exchange in functionals =
Only for BLYP series:

{{{
$scf
RKS
DFT
# new functional with cX*HF+(1-cX)*B88
VBLYP
hfexchange
0.0
charge
0
spin
1
THRESHCONV
1.d-12 1.d-10
OPTSCR
1
$end
}}}

Results:

||HF c_X ||Etot(a.u.) ||w1(eV) ||w2(eV) ||
||0.0 (BLYP) ||-114.58954137 ||3.1626 ||5.5590 ||
|| 0.5 (BHHLYP) ||  -114.54640539 || 3.3246 || 4.7647 ||
|| 1.0 (HF-LYP) || || 2.1812 || 3.4426 ||
|| ||
|| HF ||  -113.97616771 || 2.1812 || 3.4426 ||

Note that when c_X=1, it is not HF but HF-LYP.