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

Isomers of C2H4

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH3CH 4218502 methylmethylene   sketch of methylmethylene
b C2H4 74851 Ethylene 0.0 sketch of Ethylene
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM3 92.0 a
MNDOd
0.0 b
composite G1 302.8 a
0.0 b
G2MP2 300.4 a
0.0 b
G2 318.3 a
0.0 b
G3 291.1 a
0.0 b
G3B3 166.1 a
0.0 b
G3MP2 302.5 a
0.0 b
G4 178.4 a
0.0 b
CBS-Q 162.5 a
0.0 b
molecular mechanics MM3
0.0 b

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) 6-311+G(3df,2pd) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
hartree fock HF
0.0 b

0.0 b

0.0 b

0.0 b
170.2 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
177.8 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
180.5 a
0.0 b
density functional LSDA                    
0.0 b

0.0 b
     
0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
BLYP
0.0 b

0.0 b

0.0 b

0.0 b
293.0 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
B1B95
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
B3LYP
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
290.2 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
B3LYPultrafine
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
B3PW91
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
mPW1PW91
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
M06-2X
0.0 b

0.0 b
284.9 a
0.0 b

0.0 b
281.0 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
PBEPBE
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
PBEPBEultrafine
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
PBE1PBE
0.0 b

0.0 b

0.0 b

0.0 b
268.1 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
HSEh1PBE
0.0 b
271.7 a
0.0 b

0.0 b

0.0 b
267.4 a
0.0 b

0.0 b
268.2 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
273.4 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
TPSSh
0.0 b

0.0 b

0.0 b

0.0 b
264.5 a
0.0 b

0.0 b
265.3 a
0.0 b

0.0 b

0.0 b
266.2 a
0.0 b

0.0 b
 
0.0 b

0.0 b
270.0 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
wB97X-D
0.0 b

0.0 b
283.8 a
0.0 b

0.0 b
280.0 a
0.0 b

0.0 b
280.7 a
0.0 b

0.0 b
284.4 a
0.0 b

0.0 b

0.0 b
  285.2 a
0.0 b
267.8 a
0.0 b
286.5 a
0.0 b

0.0 b

0.0 b
285.9 a
0.0 b

0.0 b
       
0.0 b

0.0 b
B97D3
0.0 b
284.3 a
0.0 b

0.0 b

0.0 b
279.7 a
0.0 b

0.0 b
281.3 a
0.0 b

0.0 b
283.9 a
0.0 b

0.0 b
286.0 a
0.0 b
  285.4 a
0.0 b

0.0 b
285.9 a
0.0 b

0.0 b

0.0 b
284.8 a
0.0 b

0.0 b
       
0.0 b
 
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) 6-311+G(3df,2pd) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
Moller Plesset perturbation MP2
0.0 b

0.0 b

0.0 b

0.0 b
285.2 a
0.0 b

0.0 b

0.0 b
288.0 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
292.6 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
MP2=FULL
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
ROMP2                                                
0.0 b
MP3
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b

0.0 b
 
0.0 b

0.0 b
MP3=FULL         275.9 a
0.0 b
  278.9 a
0.0 b
                         
0.0 b

0.0 b
 
0.0 b

0.0 b
MP4
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
MP4=FULL
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
B2PLYP
0.0 b

0.0 b

0.0 b

0.0 b
286.2 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
295.3 a
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
B2PLYP=FULL
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
   
0.0 b

0.0 b
 
0.0 b

0.0 b
Configuration interaction CID
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b

0.0 b
 
0.0 b

0.0 b
CISD
0.0 b
 
0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b

0.0 b
 
0.0 b

0.0 b
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) 6-311+G(3df,2pd) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
Quadratic configuration interaction QCISD
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
QCISD(T)
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b

0.0 b
QCISD(T)=FULL                                              
0.0 b

0.0 b
QCISD(TQ)
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
 
0.0 b
               
Coupled Cluster CCD
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b

0.0 b
 
0.0 b

0.0 b
CCSD
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b

0.0 b
 
0.0 b

0.0 b
CCSD=FULL
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b

0.0 b
 
0.0 b

0.0 b
CCSD(T)
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
CCSD(T)=FULL
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
0.0 b

0.0 b
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) 6-311+G(3df,2pd) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ 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
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
    180.5 a
0.0 b
density functional LSDA
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
BLYP
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
B1B95
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
B3LYP
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
    291.0 a
0.0 b
B3LYPultrafine
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
B3PW91
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
mPW1PW91
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
M06-2X
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
PBEPBE
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
    287.5 a
0.0 b
PBEPBEultrafine
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
PBE1PBE
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
HSEh1PBE
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
TPSSh                
0.0 b
wB97X-D
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
B97D3                
0.0 b
Moller Plesset perturbation MP2
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
    301.0 a
0.0 b
MP2=FULL
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
MP3
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
MP4
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
MP4=FULL
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
B2PLYP
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b
B2PLYP=FULL                
0.0 b
Configuration interaction CID
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
CISD
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
Quadratic configuration interaction QCISD
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
QCISD(T)
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
QCISD(TQ)
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
Coupled Cluster CCD
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
CCSD
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
CCSD=FULL
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
CCSD(T)
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
     
CCSD(T)=FULL
0.0 b

0.0 b

0.0 b

0.0 b

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

0.0 b

0.0 b
   
0.0 b
MP4// HF/6-31G*          
0.0 b
MP4// B3LYP/6-31G*          
0.0 b
MP4// MP2/6-31G*
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

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

0.0 b

0.0 b

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