return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Correlation > Full vs Frozen core energies

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

For NH2CONH2 (Urea)

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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
Moller Plesset perturbation MP2=FULL -0.000966 -0.007119 -0.007119 -0.004766 -0.014761 -0.015494 -0.016131 -0.075499 -0.076127 -0.034552 -0.069101 -0.009810 -0.058576 -0.117947 -0.011343 -0.067703 -0.120312
MP3=FULL         -0.014148   -0.015533       -0.071478 -0.009130 -0.059483        
MP4=FULL   -0.006753     -0.014203       -0.078417     -0.009102 -0.059659   -0.010627 -0.069460  
B2PLYP=FULL -0.000289 -0.002105 -0.002105 -0.001407 -0.004334 -0.004544 -0.004730 -0.021434 -0.021619 -0.009969 -0.019643 -0.002882 -0.016912   -0.003335 -0.019488  
Quadratic configuration interaction QCISD(T)=FULL         -0.014161             -0.009062 -0.059599   -0.010573 -0.069402  
QCISD(TQ)=FULL         -0.014164   -0.015112         -0.009057     -0.010562 -0.069715  
Coupled Cluster CCSD=FULL         -0.014010         -0.034665 -0.071347 -0.008953 -0.059124   -0.010447 -0.068917  
CCSD(T)=FULL         -0.014166           -0.071737 -0.009064 -0.059613 -0.122529 -0.010576 -0.069418  
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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ