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

Isomers of C12H8

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C12H8 208968 Acenaphthylene 0.0 sketch of Acenaphthylene
b C12H8 259790 biphenylene 154.0 sketch of biphenylene
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM3 0.0 a
composite G1
NC
G2MP2
NC
G2
NC
G3
NC
G3B3
NC
G4
NC
CBS-Q
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 aug-cc-pVDZ aug-cc-pVTZ
hartree fock HF
NC

NC

NC

NC
0.0 a
153.4 b

NC

NC

NC

NC

NC
 
NC

NC

NC

NC

NC
density functional LSDA  
NC
   
NC

NC

NC

NC

NC

NC
   
NC

NC

NC
 
BLYP
NC

NC

NC

NC
0.0 a
140.0 b

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
B3LYP
NC

NC

NC

NC

NC

NC

NC

NC

NC
0.0 a
145.2 b
 
NC

NC

NC

NC

NC
B3LYPultrafine  
NC
   
NC

NC

NC

NC
     
NC

NC

NC

NC
 
B3PW91
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
M06-2X
NC

NC
0.0 a
165.0 b

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
PBEPBEultrafine  
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
HSEh1PBE
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
 
NC

NC

NC

NC

NC
TPSSh  
NC

NC

NC
0.0 a
140.1 b

NC
0.0 a
140.5 b

NC
  0.0 a  
NC

NC
0.0 a
140.7 b

NC
 
wB97X-D
NC

NC
0.0 a
161.5 b

NC
0.0 a
145.1 b

NC
0.0 a
145.8 b

NC
0.0 a
145.3 b

NC
  0.0 a
146.2 b
0.0 a
125.2 b
0.0 a
144.8 b

NC
0.0 a
145.3 b
B97D3   0.0 a
165.5 b
    0.0 a
152.1 b
  0.0 a
152.2 b
  0.0 a
152.3 b
  0.0 a
152.5 b
0.0 a
153.0 b
  0.0 a
151.6 b
  0.0 a
152.2 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) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ
Moller Plesset perturbation MP2
NC
               
NC
   
NC

NC

NC

NC
MP2=FULL
NC
               
NC
   
NC

NC

NC

NC
MP3                        
NC
     
MP3=FULL         0.0 a
156.6 b
             
NC
     
MP4                        
NC
     
B2PLYP
NC

NC

NC

NC

NC

NC
 
NC

NC

NC
   
NC
0.0 a
152.2 b

NC

NC
B2PLYP=FULL
NC

NC

NC

NC

NC

NC
 
NC

NC

NC
   
NC

NC

NC

NC
Configuration interaction CID  
NC

NC
 
NC
   
NC
               
CISD  
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 aug-cc-pVDZ aug-cc-pVTZ
Quadratic configuration interaction QCISD  
NC

NC
 
NC
             
NC
     
Coupled Cluster CCD  
NC

NC
                 
NC
     
CCSD                        
NC
     
CCSD=FULL        
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 aug-cc-pVDZ aug-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
NC

NC

NC

NC

NC

NC
    0.0 a
154.5 b
density functional B3LYP
NC

NC

NC

NC

NC

NC
    0.0 a
145.8 b
PBEPBE                 0.0 a
142.3 b
wB97X-D
NC

NC

NC

NC

NC

NC
     
Moller Plesset perturbation MP2        
NC

NC
    0.0 a
160.9 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.