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

Relative enthalpies of isomers - Comparison of 0K enthalpies (kJ mol-1)

Isomers of C2H2F2

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH2CF2 75387 Ethene, 1,1-difluoro- 0.0 sketch of Ethene, 1,1-difluoro-
b C2H2F2 1630779 Ethene, 1,2-difluoro-, (Z)-   sketch of Ethene, 1,2-difluoro-, (Z)-
c C2H2F2 1630780 Ethene, 1,2-difluoro-, (E)-   sketch of Ethene, 1,2-difluoro-, (E)-
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
composite G1 0.0 a
41.5 b
G2MP2 0.0 a
41.0 b
G2 0.0 a
41.8 b
43.8 c
G3 0.0 a
42.6 b
44.2 c
G3B3 0.0 a
41.4 b
43.6 c
G3MP2 0.0 a
41.9 b
CBS-Q 0.0 a
44.5 b
44.6 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
hartree fock HF 0.0 a
40.7 b
38.6 c
0.0 a
55.2 b
48.2 c
0.0 a
55.2 b
48.2 c
0.0 a
33.4 b
27.0 c
  0.0 a
49.8 b
47.6 c
0.0 a
39.4 b
40.6 c
0.0 a
47.9 b
46.8 c
0.0 a
47.0 b
45.8 c
0.0 a
53.1 b
52.8 c
0.0 a
42.3 b
45.8 c
0.0 a
40.9 b
42.3 c
0.0 a
49.0 b
47.0 c
0.0 a
45.6 b
46.9 c
0.0 a
37.9 b
40.8 c
0.0 a
41.6 b
45.0 c
0.0 a
45.6 b
density functional LSDA 0.0 a
49.3 b
49.2 c
0.0 a
62.1 b
59.8 c
0.0 a
62.1 b
59.8 c
0.0 a
46.0 b
44.0 c
0.0 a
56.2 b
56.3 c
0.0 a
55.9 b
56.0 c
0.0 a
44.6 b
47.3 c
0.0 a
54.6 b
54.9 c
0.0 a
54.1 b
54.3 c
0.0 a
57.8 b
59.0 c
    0.0 a
56.1 b
55.5 c
0.0 a
50.7 b
52.8 c
0.0 a
43.7 b
47.8 c
  0.0 a
50.7 b
52.8 c
SVWN   0.0 a
62.1 b
59.8 c
    0.0 a
56.2 b
56.3 c
  0.0 a
44.6 b
47.3 c
                   
BLYP 0.0 a
43.9 b
43.4 c
0.0 a
51.2 b
49.2 c
0.0 a
51.2 b
49.2 c
0.0 a
36.3 b
33.7 c
0.0 a
45.2 b
44.9 c
0.0 a
44.9 b
44.6 c
0.0 a
33.9 b
35.4 c
0.0 a
43.7 b
43.3 c
0.0 a
43.1 b
42.5 c
0.0 a
47.2 b
48.0 c
    0.0 a
44.9 b
44.0 c
0.0 a
40.1 b
41.3 c
    0.0 a
40.1 b
B1B95 0.0 a
43.8 b
43.5 c
0.0 a
55.6 b
52.0 c
0.0 a
55.6 b
52.0 c
0.0 a
38.4 b
35.0 c
0.0 a
39.5 b
38.8 c
0.0 a
50.4 b
49.7 c
0.0 a
39.7 b
41.5 c
0.0 a
48.6 b
48.3 c
0.0 a
48.0 b
47.6 c
      0.0 a
50.1 b
49.1 c
0.0 a
33.0 b
34.5 c
    0.0 a
33.0 b
B3LYP 0.0 a
42.9 b
42.3 c
0.0 a
53.4 b
50.1 c
0.0 a
53.4 b
50.1 c
0.0 a
36.5 b
33.1 c
0.0 a
47.6 b
46.9 c
0.0 a
47.2 b
46.5 c
0.0 a
36.1 b
37.6 c
0.0 a
45.7 b
45.1 c
0.0 a
45.0 b
44.3 c
0.0 a
49.6 b
50.2 c
  0.0 a
38.1 b
39.7 c
0.0 a
47.0 b
45.9 c
0.0 a
42.4 b
43.6 c
0.0 a
35.1 b
38.1 c
0.0 a
40.7 c
0.0 a
42.4 b
43.6 c
B3LYPultrafine         0.0 a
47.7 b
46.9 c
                       
B3PW91 0.0 a
44.1 b
43.8 c
0.0 a
55.5 b
52.3 c
0.0 a
55.5 b
52.3 c
0.0 a
38.3 b
35.0 c
0.0 a
50.3 b
49.8 c
0.0 a
49.9 b
49.3 c
0.0 a
39.2 b
41.1 c
0.0 a
47.9 b
47.8 c
0.0 a
47.3 b
47.1 c
0.0 a
51.7 b
52.7 c
    0.0 a
49.2 b
48.4 c
0.0 a
44.8 b
46.5 c
    0.0 a
44.8 b
mPW1PW91 0.0 a
44.0 b
43.5 c
0.0 a
51.6 b
48.1 c
0.0 a
56.1 b
52.6 c
0.0 a
38.5 b
35.0 c
0.0 a
47.0 b
46.3 c
0.0 a
46.5 b
45.9 c
0.0 a
35.9 b
37.8 c
0.0 a
44.6 b
44.5 c
0.0 a
48.0 b
47.7 c
0.0 a
52.5 b
53.4 c
    0.0 a
45.9 b
45.0 c
0.0 a
41.7 b
43.4 c
    0.0 a
41.7 b
M06-2X         0.0 a
53.1 b
51.0 c
                       
PBEPBE 0.0 a
46.1 b
45.9 c
0.0 a
55.0 b
53.2 c
0.0 a
55.0 b
53.2 c
0.0 a
40.0 b
37.8 c
0.0 a
49.9 b
49.9 c
0.0 a
49.5 b
49.6 c
0.0 a
38.7 b
41.0 c
0.0 a
47.9 b
48.1 c
0.0 a
47.4 b
47.4 c
0.0 a
51.0 b
52.4 c
   
NC
NC
0.0 a
44.5 b
46.5 c
    0.0 a
44.5 b
PBE1PBE         0.0 a
52.1 b
51.5 c
                       
HSEh1PBE         0.0 a
51.6 b
51.0 c
                       
TPSSh             0.0 a
36.1 b
38.0 c
                   
Moller Plesset perturbation MP2 0.0 a
40.4 b
39.1 c
0.0 a
57.6 b
53.6 c
0.0 a
57.6 b
53.6 c
0.0 a
36.8 b
32.1 c
  0.0 a
51.5 b
50.3 c
  0.0 a
52.6 b
52.3 c
0.0 a
51.2 b
51.0 c
0.0 a
57.8 b
58.0 c
  0.0 a
43.0 b
44.9 c
0.0 a
53.6 b
53.0 c
0.0 a
48.4 b
0.0 a
39.3 b
42.8 c
   
MP2=FULL
NC
NC
0.0 a
57.7 b
53.6 c

NC
NC

NC
NC
  0.0 a
52.1 b
51.0 c
0.0 a
39.6 b
41.0 c
0.0 a
53.0 b
52.7 c
0.0 a
51.5 b
51.3 c

NC
NC
    0.0 a
53.9 b
53.2 c
0.0 a
48.9 b
50.8 c
     
MP3         0.0 a
1624.9 b
45.8 c
                       
MP3=FULL         0.0 a
48.8 b
46.5 c
  0.0 a
37.4 b
37.8 c
                   
MP4  
NC
NC
    0.0 a
47.7 b
46.2 c
                       
B2PLYP         0.0 a
49.1 b
48.1 c
                0.0 a
44.3 b
45.8 c
     
Configuration interaction CID  
NC
NC

NC
NC

NC
NC
0.0 a
49.5 b
47.3 c
   
NC
NC
                 
CISD  
NC
NC

NC
NC

NC
NC

NC
NC
   
NC
NC
                 
Quadratic configuration interaction QCISD
NC
NC
0.0 a
52.4 b
47.8 c

NC
NC

NC
NC
0.0 a
46.8 b
44.8 c
0.0 a
46.2 b
44.5 c
0.0 a
34.8 b
35.3 c
0.0 a
47.8 b
46.9 c
0.0 a
45.8 b
45.1 c

NC
NC
   
NC
NC

NC
NC
   
NC
NC
QCISD(T)        
NC
NC
     
NC
NC
               
Coupled Cluster CCD
NC
NC

NC
NC

NC
NC

NC
NC
0.0 a
47.2 b
44.8 c

NC
NC
0.0 a
35.6 b
35.8 c

NC
NC

NC
NC

NC
NC
    0.0 a
48.8 b
47.3 c
0.0 a
44.5 b
45.7 c
     
CCSD                
NC
NC
               
CCSD(T)         0.0 a
47.4 b
45.2 c
     
NC
NC
               

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 0.0 a
17.2 b
12.8 c
0.0 a
36.7 b
36.9 c
0.0 a
20.9 b
16.8 c
0.0 a
39.8 b
40.1 c
0.0 a
24.2 b
18.9 c
0.0 a
24.6 b
19.2 c
density functional B1B95 0.0 a
26.4 b
24.0 c
0.0 a
41.3 b
42.1 c
       
B3LYP 0.0 a
23.4 b
20.5 c
0.0 a
37.1 b
37.7 c
0.0 a
23.8 b
21.1 c
0.0 a
37.3 b
37.9 c
0.0 a
29.4 b
26.1 c
0.0 a
29.8 b
26.6 c
Moller Plesset perturbation MP2 0.0 a
20.8 b
16.8 c
0.0 a
39.7 b
40.2 c
0.0 a
23.1 b
19.4 c
0.0 a
41.1 b
41.6 c
0.0 a
27.3 b
22.7 c
0.0 a
27.6 b
23.0 c

Single point energy calculations (select basis sets)
cc-pVTZ aug-cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2FC// MP2FC/6-31G*   0.0 a
42.9 b
 
Coupled Cluster CCSD(T)//B3LYP/6-31G(2df,p) 0.0 a
44.1 b
  0.0 a
44.1 b
CCSD// MP2FC/6-31G*   0.0 a
39.6 b
 
CCSD(T)// MP2FC/6-31G*   0.0 a
39.8 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.