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Relative enthalpies of isomers - Comparison of 298.15K enthalpies (kJ mol-1)

Isomers of CHO2

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a HOCO 2564865 Hydrocarboxyl radical   sketch of Hydrocarboxyl radical
b HCOO 9000392 formate neutral radical   sketch of formate neutral radical
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM3
-127.3 b
composite G1 NC
NC
G2MP2 NC
NC
G2 NC
NC
G3 NC
NC
G3B3 NC
NC
G4 NC
CBS-Q NC
NC

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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ daug-cc-pVDZ daug-cc-pVTZ
hartree fock HF NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC   NC NC
NC
ROHF   NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
  NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
    NC NC
density functional LSDA NC
NC

NC

NC
NC
NC
NC
NC

NC

NC
NC
NC

NC

NC
 
NC

NC

NC

NC

NC

NC
  NC      
BLYP NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC NC   NC   NC NC
B1B95 NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC

NC
NC
NC
NC
NC

NC
NC   NC NC
B3LYP NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC   NC NC
B3LYPultrafine   NC     NC
NC
NC NC NC   NC NC NC NC
NC
NC
NC
  NC
NC
NC
NC
      NC NC
B3PW91 NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC NC   NC   NC NC
mPW1PW91 NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
  NC   NC NC
M06-2X NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
      NC NC
PBEPBE NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC

NC
NC
NC
NC
NC

NC
NC   NC NC
PBEPBEultrafine   NC     NC
NC
NC NC NC   NC NC NC NC
NC
NC
NC
  NC
NC
NC
NC
      NC NC
PBE1PBE NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
      NC NC
HSEh1PBE NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
      NC NC
TPSSh NC NC NC NC NC
NC
NC NC
NC
NC NC NC
NC
NC NC NC NC
NC
NC NC NC NC     NC NC
wB97X-D NC NC NC
NC
NC NC
NC
NC NC
NC
NC NC
NC
NC NC NC
NC
NC
NC
NC
NC
NC NC NC
NC
NC     NC NC
B97D3 NC NC
NC
NC NC NC
NC
NC NC
NC
NC NC
NC
NC NC
NC
NC
NC
NC NC
NC
NC NC NC
NC
NC     NC  
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ daug-cc-pVDZ daug-cc-pVTZ
Moller Plesset perturbation MP2
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC NC NC
MP2=FULL
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC NC NC
ROMP2 NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC
NC
        NC NC
MP3         NC
NC
  NC       NC NC NC NC             NC  
MP3=FULL   NC NC NC NC
NC
NC NC
NC
NC NC NC NC NC NC NC   NC NC       NC  
MP4   NC
NC
    NC
NC
      NC
NC
  NC NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
      NC NC
MP4=FULL   NC
NC
    NC
NC
      NC
NC
  NC   NC
NC
NC
NC
  NC
NC
NC
NC
      NC NC
B2PLYP NC NC NC NC NC NC NC NC NC NC NC NC NC NC   NC NC       NC NC
B2PLYP=FULL NC NC NC NC NC NC NC NC NC NC NC NC NC NC   NC NC       NC NC
Configuration interaction CID   NC
NC
NC
NC
NC
NC
NC
NC
    NC
NC
    NC   NC NC             NC  
CISD   NC
NC
NC
NC
NC
NC
NC
NC
    NC
NC
    NC   NC NC             NC  
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ daug-cc-pVDZ daug-cc-pVTZ
Quadratic configuration interaction QCISD   NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
  NC      
QCISD(T)         NC
NC
    NC     NC NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
  NC   NC NC
QCISD(T)=FULL         NC   NC       NC   NC NC NC NC NC NC     NC NC
Coupled Cluster CCD   NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
  NC   NC  
CCSD         NC
NC
NC NC NC NC NC NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
      NC  
CCSD=FULL         NC
NC
        NC NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
      NC  
CCSD(T)         NC
NC
NC NC NC NC NC NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC   NC NC
CCSD(T)=FULL         NC
NC
          NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC     NC NC
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ daug-cc-pVDZ daug-cc-pVTZ

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF -97866.1 a
-97944.5 b
-98122.9 a
-98193.4 b
-97882.2 a
-97958.2 b
-98141.0 a
-98206.7 b
NC
NC
NC
NC
    NC
NC
ROHF                 NC
density functional BLYP                 NC
B1B95                 NC
B3LYP -99878.9 a
-99901.0 b
NC
NC
-99894.0 a
-99917.4 b
NC
NC
NC
NC
NC
NC
    NC
NC
B3LYPultrafine                 NC
B3PW91                 NC
mPW1PW91                 NC
M06-2X                 NC
PBEPBE                 NC
NC
PBEPBEultrafine                 NC
PBE1PBE                 NC
HSEh1PBE                 NC
TPSSh                 NC
wB97X-D -99844.0 a NC -99859.7 a NC NC NC     NC
B97D3                 NC
Moller Plesset perturbation MP2 -98631.1 a
-98619.9 b
-99302.2 a
-99285.9 b
-98739.9 a
-98728.6 b
-99392.4 a
-99373.3 b
NC
NC
NC
NC
    NC
NC
MP2=FULL                 NC
ROMP2                 NC
MP3                 NC
MP3=FULL                 NC
MP4                 NC
MP4=FULL                 NC
B2PLYP                 NC
B2PLYP=FULL                 NC
Configuration interaction CID                 NC
CISD                 NC
Quadratic configuration interaction QCISD                 NC
QCISD(T)=FULL                 NC
Coupled Cluster CCD                 NC
CCSD                 NC
CCSD=FULL                 NC
CCSD(T)                 NC
CCSD(T)=FULL                 NC
NC = not calculated
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.
gaw refers to the group additivity method implemeted in the NIST Chemistry Webbook.
See section Calculated; Vibrations; Scale Factors; Scale factors to list vibrational scaling factors.
See section Calculated; Vibrations; Scale Factors; Calculate a scale factor to calculate a vibrational scaling factor for a given set of molecules.