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

Isomers of C2H3N

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH3CN+ 75058 Acetonitrile cation   sketch of Acetonitrile cation
b HCNCH2+ 157164 2H-Azirine cation   sketch of 2H-Azirine cation
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM3 1254.5 a
PM6 1430.2 a
1095.1 b
composite G1 NC
NC
G2MP2 NC
NC
G2 NC
NC
G3 NC
NC
G3B3 NC
NC
G4 NC
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) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ daug-cc-pVTZ
hartree fock HF 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  
density functional B3LYP NC                              
B3PW91 NC                              
mPW1PW91 NC                 NC     NC NC NC  
M06-2X NC     NC NC NC NC NC NC NC   NC NC NC NC  
PBE1PBE         NC                      
HSEh1PBE NC                 NC       NC    
wB97X-D                 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) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ daug-cc-pVTZ
Moller Plesset perturbation MP2         NC NC NC NC NC NC NC NC NC NC NC  
MP2=FULL         NC NC NC NC NC NC   NC NC NC NC  
MP3         NC   NC                  
MP3=FULL         NC   NC                  
MP4         NC       NC       NC      
Configuration interaction CID   NC NC NC NC     NC                
CISD   NC NC NC NC     NC                
Coupled Cluster CCD   NC NC NC NC NC NC NC NC NC   NC NC NC NC  
CCSD         NC             NC NC      
CCSD(T)         NC             NC NC NC    
CCSD(T)=FULL         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) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ 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 -57446.4 a -57638.6 a -57465.8 a -57662.5 a NC NC     NC
Moller Plesset perturbation MP2   -58517.5 a   -58608.6 a         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.