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

Isomers of C2H2F2

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C2H2F2 1630779 Ethene, 1,2-difluoro-, (Z)-   sketch of Ethene, 1,2-difluoro-, (Z)-
b C2H2F2 1630780 Ethene, 1,2-difluoro-, (E)-   sketch of Ethene, 1,2-difluoro-, (E)-
c CH2CF2 75387 Ethene, 1,1-difluoro- 0.0 sketch of Ethene, 1,1-difluoro-
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1
0.0 c
PM3 27.7 a
130.3 b
0.0 c
MNDOd
0.0 c
composite G1 41.8 a
44.2 b
0.0 c
G2MP2 41.4 a
43.9 b
0.0 c
G2 42.2 a
44.5 b
0.0 c
G3 43.0 a
44.8 b
0.0 c
G3B3 41.8 a
44.3 b
0.0 c
G3MP2 42.2 a
44.4 b
0.0 c
G4 41.4 a
44.5 b
0.0 c
CBS-Q 43.6 a
149.7 b
0.0 c
molecular mechanics MM3
0.0 c

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 cc-pV(T+d)Z daug-cc-pVTZ
hartree fock HF 40.9 a
39.0 b
0.0 c
55.6 a
48.9 b
0.0 c
55.6 a
48.8 b
0.0 c
33.7 a
27.6 b
0.0 c
50.9 a
49.0 b
0.0 c
50.1 a
48.3 b
0.0 c
39.7 a
41.3 b
0.0 c
48.3 a
47.5 b
0.0 c
47.3 a
46.5 b
0.0 c
53.5 a
53.5 b
0.0 c
42.6 a
46.4 b
0.0 c
41.4 a
43.0 b
0.0 c
49.3 a
47.7 b
0.0 c
46.0 a
47.5 b
0.0 c
38.3 a
41.5 b
0.0 c
41.9 a
45.6 b
0.0 c
46.0 a
0.0 c
42.2 a
46.0 b
0.0 c
density functional LSDA NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
    NC
NC
NC
NC
NC
NC
  NC
NC
 
BLYP 43.9 a
43.8 b
0.0 c
51.5 a
49.8 b
0.0 c
51.5 a
49.8 b
0.0 c
36.6 a
34.3 b
0.0 c
45.6 a
45.5 b
0.0 c
45.2 a
45.2 b
0.0 c
34.2 a
36.0 b
0.0 c
44.0 a
43.9 b
0.0 c
43.4 a
43.1 b
0.0 c
47.6 a
48.6 b
0.0 c
    45.2 a
44.6 b
0.0 c
40.4 a
41.9 b
0.0 c

0.0 c
  40.4 a
0.0 c
 
B1B95 44.0 a
43.9 b
0.0 c
55.8 a
52.7 b
0.0 c
55.8 a
52.7 b
0.0 c
38.6 a
35.6 b
0.0 c
39.9 a
39.4 b
0.0 c
50.7 a
50.3 b
0.0 c
40.0 a
42.1 b
0.0 c
48.9 a
48.9 b
0.0 c
48.3 a
48.2 b
0.0 c

0.0 c
    50.4 a
49.7 b
0.0 c
33.4 a
35.1 b
0.0 c

0.0 c
41.6 a
0.0 c
33.4 a
0.0 c
 
B3LYP 43.0 a
42.7 b
0.0 c
53.7 a
50.7 b
0.0 c
53.7 a
50.7 b
0.0 c
36.8 a
33.7 b
0.0 c
48.0 a
47.5 b
0.0 c
47.5 a
47.0 b
0.0 c
36.4 a
38.2 b
0.0 c
46.0 a
45.7 b
0.0 c
45.4 a
45.0 b
0.0 c
50.0 a
50.8 b
0.0 c

0.0 c
38.5 a
40.3 b
0.0 c
47.3 a
46.5 b
0.0 c
42.7 a
44.2 b
0.0 c
35.4 a
38.7 b
0.0 c
-40.0 a
41.4 b
0.0 c
42.7 a
44.2 b
0.0 c
 
B3LYPultrafine         48.0 a
47.5 b
0.0 c
 
0.0 c
           
0.0 c
  37.9 a
0.0 c
   
B3PW91 44.2 a
44.2 b
0.0 c
55.7 a
52.9 b
0.0 c
55.7 a
52.9 b
0.0 c
38.5 a
35.6 b
0.0 c
50.7 a
50.4 b
0.0 c
50.2 a
49.9 b
0.0 c
39.5 a
41.7 b
0.0 c
48.3 a
48.4 b
0.0 c
47.7 a
47.7 b
0.0 c
52.1 a
53.3 b
0.0 c
    49.6 a
49.0 b
0.0 c
45.1 a
47.1 b
0.0 c

0.0 c

0.0 c
45.1 a
0.0 c
 
mPW1PW91 44.1 a
43.9 b
0.0 c
51.9 a
48.8 b
0.0 c
56.4 a
53.3 b
0.0 c
38.8 a
35.6 b
0.0 c
47.3 a
46.9 b
0.0 c
46.8 a
46.5 b
0.0 c
36.2 a
38.5 b
0.0 c
45.0 a
45.1 b
0.0 c
48.4 a
48.4 b
0.0 c
52.9 a
54.0 b
0.0 c
    46.2 a
45.6 b
0.0 c
42.1 a
44.1 b
0.0 c

0.0 c
  42.1 a
0.0 c
 
M06-2X     55.6 a
50.4 b
0.0 c
  53.4 a
51.6 b
0.0 c
       
0.0 c
     
0.0 c
 
0.0 c
   
PBEPBE 46.2 a
46.4 b
0.0 c
55.3 a
53.8 b
0.0 c
55.3 a
53.8 b
0.0 c
40.2 a
38.4 b
0.0 c
50.2 a
50.5 b
0.0 c
49.8 a
50.1 b
0.0 c
39.0 a
41.6 b
0.0 c
48.3 a
48.8 b
0.0 c
47.7 a
48.1 b
0.0 c
51.4 a
53.0 b
0.0 c
    NC
NC
44.8 a
47.1 b
0.0 c

0.0 c

0.0 c
44.8 a
0.0 c
 
PBEPBEultrafine        
0.0 c
                         
PBE1PBE         52.4 a
52.1 b
0.0 c
                         
HSEh1PBE   57.0 a
53.9 b
0.0 c
    52.0 a
51.6 b
0.0 c
  40.6 a
42.9 b
0.0 c
            46.5 a
48.5 b
0.0 c
       
TPSSh         47.8 a
47.6 b
0.0 c
  36.4 a
38.6 b
0.0 c
    48.8 a
50.2 b
0.0 c
      41.8 a
43.9 b
0.0 c
       
wB97X-D     56.8 a
53.2 b
0.0 c
  51.4 a
50.6 b
0.0 c
  39.9 a
41.6 b
0.0 c
  48.2 a
47.7 b
0.0 c
    41.7 a
43.5 b
0.0 c
39.9 a
41.6 b
0.0 c
45.8 a
47.3 b
0.0 c
  41.5 a
45.0 b
0.0 c
   
B97D3   52.4 a
50.8 b
0.0 c
    47.4 a
47.6 b
0.0 c
  36.8 a
39.1 b
0.0 c
  44.8 a
45.1 b
0.0 c
  38.5 a
42.6 b
0.0 c
38.7 a
41.2 b
0.0 c
  42.4 a
44.6 b
0.0 c
  38.0 a
42.0 b
0.0 c
   
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 cc-pV(T+d)Z daug-cc-pVTZ
Moller Plesset perturbation MP2 40.5 a
39.5 b
0.0 c
57.9 a
54.3 b
0.0 c
57.9 a
54.3 b
0.0 c
37.0 a
32.7 b
0.0 c
51.9 a
50.7 b
0.0 c
51.8 a
50.9 b
0.0 c
  52.9 a
52.9 b
0.0 c
51.5 a
51.7 b
0.0 c
58.2 a
58.6 b
0.0 c
  43.4 a
45.5 b
0.0 c
54.0 a
53.6 b
0.0 c
48.7 a
0.0 c
39.6 a
43.4 b
0.0 c
43.4 a
0.0 c

0.0 c
 
MP2=FULL NC
NC
57.9 a
54.3 b
0.0 c
NC
NC
NC
NC
52.5 a
51.4 b
0.0 c
52.4 a
51.6 b
0.0 c
39.9 a
41.6 b
0.0 c
53.3 a
53.3 b
0.0 c
51.8 a
52.0 b
0.0 c
60.1 a
60.9 b
0.0 c
    54.2 a
53.8 b
0.0 c
49.2 a
51.4 b
0.0 c
 
0.0 c
NC  
MP3         1625.3 a
46.4 b
0.0 c
 
0.0 c
                     
MP3=FULL         49.2 a
47.1 b
0.0 c
  37.6 a
38.4 b
0.0 c
                     
MP4   NC
NC
    48.0 a
46.7 b
0.0 c
                         
B2PLYP         49.4 a
48.7 b
0.0 c
       
0.0 c
      44.7 a
46.5 b
0.0 c
 
0.0 c
   
Configuration interaction CID   NC
NC
NC
NC
NC
NC
49.8 a
47.9 b
0.0 c
    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 aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z daug-cc-pVTZ
Quadratic configuration interaction QCISD NC
NC
52.7 a
48.5 b
0.0 c
NC
NC
NC
NC
47.2 a
45.4 b
0.0 c
46.5 a
45.1 b
0.0 c
35.0 a
35.9 b
0.0 c
48.2 a
47.5 b
0.0 c
46.1 a
45.7 b
0.0 c
53.3 a
53.2 b
0.0 c
    NC
NC
44.3 a
46.1 b
0.0 c
 
0.0 c
NC
NC
 
QCISD(T)         NC
NC
      NC
NC
                 
Coupled Cluster CCD NC
NC
NC
NC
NC
NC
NC
NC
47.5 a
45.4 b
0.0 c
NC
NC
35.9 a
36.4 b
0.0 c
NC
NC
NC
NC
NC
NC
    49.2 a
47.9 b
0.0 c
44.8 a
46.3 b
0.0 c

0.0 c

0.0 c
NC  
CCSD        
0.0 c
      NC
NC

0.0 c
     
0.0 c
 
0.0 c
   
CCSD=FULL        
0.0 c
       
0.0 c
     
0.0 c
 
0.0 c
   
CCSD(T)         47.7 a
45.8 b
0.0 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 aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z 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 17.5 a
13.3 b
0.0 c
37.0 a
37.5 b
0.0 c
21.2 a
17.4 b
0.0 c
40.1 a
40.7 b
0.0 c
24.5 a
19.5 b
0.0 c
24.8 a
19.8 b
0.0 c
    44.0 a
46.4 b
0.0 c
density functional B1B95 26.6 a
24.5 b
0.0 c
41.5 a
42.6 b
0.0 c
             
B3LYP 23.6 a
21.0 b
0.0 c
37.3 a
38.2 b
0.0 c
24.0 a
21.6 b
0.0 c
37.6 a
38.5 b
0.0 c
29.6 a
26.7 b
0.0 c
30.0 a
27.1 b
0.0 c
    40.4 a
42.7 b
0.0 c
PBEPBE                 42.6 a
45.6 b
0.0 c
Moller Plesset perturbation MP2 20.9 a
17.3 b
0.0 c
40.0 a
40.7 b
0.0 c
23.3 a
19.9 b
0.0 c
41.3 a
42.1 b
0.0 c
27.5 a
23.3 b
0.0 c
27.8 a
23.6 b
0.0 c
    46.3 a
49.5 b
0.0 c

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

0.0 c

0.0 c

0.0 c

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

0.0 c

0.0 c

0.0 c

0.0 c
MP2FC// MP2FC/6-31G*  
0.0 c

0.0 c

0.0 c

0.0 c
MP4// HF/6-31G*
0.0 c

0.0 c

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

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

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

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

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

0.0 c
     
CCSD(T)//B3LYP/6-31G(2df,p)     44.6 a
0.0 c
  44.6 a
0.0 c
CCSD// MP2FC/6-31G*  
0.0 c

0.0 c

0.0 c

0.0 c
CCSD(T)// MP2FC/6-31G*  
0.0 c

0.0 c

0.0 c

0.0 c
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.