return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Comparisons > Energy > Similar molecules > Isomers OR FAQ Help > List > Similar molecules > Isomers

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

Isomers of C6H4F2

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C6H4F2 372189 metadifluorobenzene 0.0 sketch of metadifluorobenzene
b C6H4F2 540363 1,4-difluorobenzene 2.5 sketch of 1,4-difluorobenzene
c C6H4F2 367113 orthodifluorobenzene 26.2 sketch of orthodifluorobenzene
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM3 0.0 a
0.2 b
225.0 c
PM6
-88.4 b
composite G1
NC
NC
G2MP2
NC
NC
G2
NC
NC
G3
NC
NC
G3B3
NC
NC
G3MP2
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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ daug-cc-pVTZ
hartree fock HF
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
 
NC
NC

NC

NC

NC
NC

NC

NC

NC
NC

NC
NC
density functional LSDA
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
   
NC

NC
 
NC
     
BLYP
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
   
NC

NC
         
B1B95
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
   
NC

NC
 
NC

NC
   
B3LYP
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
 
NC
NC

NC

NC

NC
NC

NC

NC

NC
NC
 
B3LYPultrafine        
NC
                     
NC
NC
   
B3PW91
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
         
M06-2X     0.0 a
18.1 c
 
NC
NC
                           
PBEPBE
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
   
NC

NC
         
PBE1PBE        
NC
NC
                           
HSEh1PBE  
NC
   
NC
 
NC
NC
           
NC
         
TPSSh        
NC
NC
 
NC
NC
   
NC
     
NC
NC
         
wB97X-D    
NC
 
NC
 
NC
 
NC
   
NC

NC

NC
   
NC
   
B97D3  
NC
   
NC
 
NC
 
NC
 
NC
0.0 a
15.6 c
 
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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ daug-cc-pVTZ
Moller Plesset perturbation MP2
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
   
NC

NC
 
NC
     
MP2=FULL
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
   
NC

NC
 
NC
     
MP3        
NC
NC
                           
MP3=FULL        
NC
NC
 
NC
NC
                       
MP4  
NC
   
NC
     
NC
                   
B2PLYP        
NC
NC
               
NC
NC
         
Configuration interaction CID  
NC
NC

NC
NC

NC
NC

NC
NC
   
NC
NC
                     
CISD  
NC
NC

NC
NC

NC
NC

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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ daug-cc-pVTZ
Quadratic configuration interaction QCISD  
NC
NC

NC
NC

NC
NC

NC
NC

NC
NC

NC
NC

NC
       
NC
NC
           
Coupled Cluster CCD  
NC
NC

NC
NC

NC
NC

NC
NC

NC
NC

NC
NC

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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ 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
NC

NC

NC

NC

NC

NC
   
NC
density functional B3LYP
NC

NC

NC

NC

NC

NC
   
NC
PBEPBE                
NC
Moller Plesset perturbation MP2
NC

NC
   
NC

NC
   
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.