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IV.A.4. (XIV.F.)

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

Isomers of C3H5

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH3CHCH 6067681 1-propenyl radical   sketch of 1-propenyl radical
b C3H5 1981802 Allyl radical 0.0 sketch of Allyl radical
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1 88.1 a
0.0 b
PM3 -84.2 a
0.0 b
PM6 -251.1 a
0.0 b
composite G1 -445.7 a
0.0 b
G2MP2 -446.4 a
0.0 b
G2 -446.1 a
0.0 b
G3 -445.5 a
0.0 b
G3B3 -77.2 a
0.0 b
G3MP2
0.0 b
G4 -77.5 a
0.0 b
CBS-Q -75.8 a
0.0 b

Methods with standard basis sets
6-31G** 6-311+G(3df,2p) cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z
hartree fock HF  
0.0 b
       
0.0 b
ROHF            
0.0 b
density functional LSDA            
0.0 b
BLYP        
0.0 b
 
0.0 b
B1B95            
0.0 b
B3LYP  
0.0 b
       
0.0 b
B3PW91        
0.0 b
 
0.0 b
mPW1PW91            
0.0 b
PBEPBE  
0.0 b
       
0.0 b
Moller Plesset perturbation MP2            
0.0 b
Coupled Cluster CCSD(T)
0.0 b
           

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
density functional B1B95
0.0 b

0.0 b
       

Single point energy calculations (select basis sets)
6-311+G(3df,2p) cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2FC// HF/6-31G*
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
MP2FC// B3LYP/6-31G*
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
MP2FC// MP2FC/6-31G*
0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b
MP4// HF/6-31G*
0.0 b

0.0 b

0.0 b
   
0.0 b
MP4// B3LYP/6-31G*  
0.0 b

0.0 b
   
0.0 b
MP4// MP2/6-31G*
0.0 b
 
0.0 b
   
0.0 b
Coupled Cluster CCSD// HF/6-31G*
0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b
CCSD(T)// HF/6-31G*
0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b
CCSD// B3LYP/6-31G*
0.0 b

0.0 b

0.0 b
   
0.0 b
CCSD(T)// B3LYP/6-31G*
0.0 b

0.0 b

0.0 b
   
0.0 b
CCSD(T)//B3LYP/6-31G(2df,p)    
0.0 b
   
0.0 b
CCSD// MP2FC/6-31G*
0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b
CCSD(T)// MP2FC/6-31G*
0.0 b

0.0 b

0.0 b

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 III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.