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Energy differences between frozen core and all electrons correlated.
MP2, MP3, MP4, B2PLYP, CCSD, and CCSD(T)

For NH2NO2 (nitramide)

Energies in Hartree
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ
Moller Plesset perturbation MP2=FULL -0.000620 -0.007249 -0.007249 -0.004466 -0.012042 -0.012403 -0.013466 -0.075287 -0.075594 -0.032568 -0.068825 -0.009057 -0.055532 -0.010427 -0.064867
MP3=FULL         -0.011296   -0.012712       -0.070777 -0.008357 -0.056164    
MP4=FULL   -0.006772     -0.011254       -0.077263     -0.008267 -0.055841 -0.009603 -0.065749
B2PLYP=FULL -0.000180 -0.002131 -0.002131 -0.001310 -0.003521 -0.003625 -0.003931 -0.021284 -0.021377 -0.009365 -0.019487 -0.002646 -0.016004 -0.003046 -0.018626
Quadratic configuration interaction QCISD(T)=FULL         -0.011223             -0.008238 -0.055902 -0.009569 -0.065850
Coupled Cluster CCSD=FULL         -0.011128         -0.032533 -0.070560 -0.008157 -0.055602 -0.009475 -0.065576
CCSD(T)=FULL         -0.011236           -0.070942 -0.008266 -0.055936 -0.009577 -0.065890
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ