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

Isomers of C2H3O

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH2CHO 4400015 Vinyloxy radical   sketch of Vinyloxy radical
b CH3CO 3170692 Acetyl radical 0.0 sketch of Acetyl radical
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1
0.0 b
PM3
0.0 b
PM6 77.7 a
0.0 b
composite G1 23.7 a
0.0 b
G2MP2 25.0 a
0.0 b
G2 24.5 a
0.0 b
G3 21.3 a
0.0 b
G3B3 22.2 a
0.0 b
G3MP2
0.0 b
G4 24.2 a
0.0 b
CBS-Q 23.6 a
0.0 b

Methods with standard basis sets
STO-3G 6-31G 6-31G* 6-311G* cc-pVTZ cc-pV(T+d)Z
hartree fock HF          
0.0 b
ROHF          
0.0 b
density functional LSDA
0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b
BLYP          
0.0 b
B1B95          
0.0 b
B3LYP          
0.0 b
B3PW91          
0.0 b
mPW1PW91          
0.0 b
PBEPBE          
0.0 b
STO-3G 6-31G 6-31G* 6-311G* cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2          
0.0 b
MP2=FULL          
0.0 b
Configuration interaction CID          
0.0 b
CISD          
0.0 b
Coupled Cluster CCSD(T)          
0.0 b
STO-3G 6-31G 6-31G* 6-311G* cc-pVTZ cc-pV(T+d)Z

Single point energy calculations (select basis sets)
cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2FC// HF/6-31G*  
0.0 b
MP2FC// B3LYP/6-31G*  
0.0 b
MP4// HF/6-31G*  
0.0 b
MP4// B3LYP/6-31G*  
0.0 b
MP4// MP2/6-31G*  
0.0 b
Coupled Cluster CCSD(T)// HF/6-31G*  
0.0 b
CCSD(T)// B3LYP/6-31G*  
0.0 b
CCSD(T)//B3LYP/6-31G(2df,p)
0.0 b

0.0 b
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.