Table 5.

Correlation energies of molecules obtained by various model correlation energy functionals. Reproduced with permission from [82]. Copyright 1998, Elsevier Science Ltd.

Molecule	WL	LYP	LW	PW	Exp
H2	0.049	0.038	0.029	0.046	0.041
Li2	0.136	0.133	0.134	0.137	0.122
Be2	0.231	0.200	0.193	0.205	0.205
B2	0.336	0.289	0.265	0.296	0.330
C2	0.446	0.384	0.344	0.391	0.514
N2	0.532	0.483	0.435	0.490	0.546
O2	0.621	0.583	0.533	0.588	0.657
F2	0.683	0.675	0.633	0.671	0.746
H2O	0.386	0.340	0.314	0.347	0.367
NH3	0.376	0.318	0.268	0.338	0.338
CH4	0.369	0.294	0.241	0.320	0.293
HF	0.377	0.363	0.335	0.367	0.387
LiH	0.088	0.089	0.083	0.092	0.083
LiF	0.417	0.418	0.343	0.415	0.447
HCN	0.525	0.464	0.410	0.478	0.527
CO	0.516	0.484	0.440	0.488	0.550
H2O2	0.690	0.638	0.569	0.652	0.691
C2H2	0.504	0.443	0.386	0.466	0.476
C2H6	0.678	0.551	0.426	0.577	0.553
C2H4	0.593	0.497	0.417	0.529	0.528
CO2	0.865	0.791	0.720	0.807	0.829