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

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

Isomers of C3H4O2

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C3H4O2 78988 Methyl glyoxal   sketch of Methyl glyoxal
b C3H4O2 542789 propanedial   sketch of propanedial
c C3H4O2 9000128 propenalol   sketch of propenalol
d HOCHCCHOH 9000400 allenediol   sketch of allenediol
e C3H4O2 79107 2-Propenoic acid 0.0 sketch of 2-Propenoic acid
f C3H4O2 57578 β–Propiolactone 26.4 sketch of β–Propiolactone
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1 207.7 a
190.0 b
195.0 c
283.3 d
0.0 e
92.5 f
PM3 2.3 a
-2.7 b
19.4 c
123.9 d
0.0 e
53.1 f
PM6 47.0 a
45.6 b
23.1 c
88.1 d
0.0 e
39.6 f
MNDOd
0.0 e
28.3 f
composite G1 NC
NC
NC
NC
G2MP2 NC
NC
NC
NC
G2 NC
NC
NC
NC
G3 -340.7 a
-134.1 b
-140.7 c
-195.0 d
0.0 e
49.4 f
G3B3 42.9 a
62.0 b
48.4 c
0.0 e
41.6 f
G3MP2
-133.7 b
-140.0 c
0.0 e
52.0 f
G4 41.3 a
59.8 b
47.7 c
188.2 d
0.0 e
40.4 f
CBS-Q 41.1 a
61.8 b
48.5 c
169.4 d
0.0 e
39.0 f
Group additivity gaw
-283.0 f
molecular mechanics MM3
0.0 e
-85.6 f

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) cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z
hartree fock HF
2.7 b
27.6 c
0.0 e
-108.3 f

80.1 b
50.2 c
0.0 e
60.3 f

80.1 b
50.2 c
0.0 e
60.2 f

72.6 b
52.6 c
0.0 e
91.9 f
 
58.3 b
58.2 c
0.0 e
48.0 f

  b
  c

44.1 b
61.4 c
0.0 e
39.7 f

0.0 e
54.4 f

56.8 b
59.6 c
0.0 e
43.5 f

58.0 b
59.8 c
0.0 e
50.4 f

57.3 b
58.0 c
0.0 e
54.5 f

60.3 b
60.1 c
0.0 e
52.4 f

55.9 b
57.4 c
0.0 e
51.8 f

0.0 e
51.7 f

60.3 b
60.1 c
0.0 e
52.4 f
density functional LSDA
40.5 b
-109.6 c
0.0 e
-130.6 f

77.0 b
-30.9 c
0.0 e
-1.4 f

77.0 b
-30.9 c
0.0 e
-1.4 f

76.8 b
-8.1 c
0.0 e
23.3 f

66.3 b
-5.7 c
0.0 e
-11.2 f

76.9 b
-13.6 c
0.0 e
-0.0 f

79.2 b
-6.8 c
0.0 e
9.2 f

66.8 b
7.7 c
0.0 e
-0.6 f

81.4 b
-3.5 c
0.0 e
14.2 f

78.2 b
-13.2 c
0.0 e
-2.2 f
 
79.3 b
-15.7 c
0.0 e
5.3 f

83.3 b
-4.9 c
0.0 e
13.4 f

80.5 b
-8.2 c
0.0 e
10.4 f
 
83.3 b
-4.9 c
0.0 e
13.4 f
BLYP
21.5 b
-72.4 c
0.0 e
-98.9 f

57.6 b
-3.2 c
0.0 e
19.0 f

57.6 b
-3.2 c
0.0 e
19.0 f

57.6 b
18.1 c
0.0 e
47.0 f

44.5 b
19.8 c
0.0 e
19.7 f

55.2 b
18.4 c
0.0 e
30.4 f

58.3 b
25.3 c
0.0 e
40.9 f

47.0 b
28.5 c
0.0 e
31.4 f

0.0 e
44.5 f

56.9 b
19.5 c
0.0 e
29.6 f
 
58.4 b
16.6 c
0.0 e
36.8 f

  b
  c

0.0 e
42.0 f
 
  b
  c
B1B95
0.0 e
-112.6 f

0.0 e
13.6 f

0.0 e
13.6 f

0.0 e
41.5 f

0.0 e
3.3 f

0.0 e
15.2 f

65.1 b
33.0 c
0.0 e
22.9 f

0.0 e
11.1 f

0.0 e
25.5 f

0.0 e
12.5 f
 
0.0 e
19.9 f

0.0 e
23.1 f

0.0 e
22.2 f
 
0.0 e
23.1 f
B3LYP
18.2 b
-55.9 c
0.0 e
-103.9 f

63.2 b
11.5 c
0.0 e
24.8 f

63.2 b
11.5 c
0.0 e
24.8 f

62.4 b
27.1 c
0.0 e
53.0 f

48.8 b
29.0 c
0.0 e
18.5 f

59.9 b
28.1 c
0.0 e
29.9 f

63.1 b
32.9 c
0.0 e
39.5 f

50.7 b
36.2 c
0.0 e
29.3 f

0.0 e
43.1 f

61.5 b
29.0 c
0.0 e
28.9 f

0.0 e
42.2 f

61.6 b
26.7 c
0.0 e
36.2 f

-103.9 b
34.0 c
0.0 e
43.0 f

64.5 b
31.3 c
0.0 e
40.6 f
 
-103.9 b
34.0 c
0.0 e
43.0 f
B3LYPultrafine        
0.0 e
18.5 f
                     
B3PW91
16.8 b
-57.4 c
0.0 e
-112.4 f

65.8 b
8.6 c
0.0 e
14.8 f

65.8 b
8.6 c
0.0 e
14.8 f

63.8 b
26.1 c
0.0 e
42.7 f

50.7 b
28.1 c
0.0 e
5.9 f

62.2 b
26.4 c
0.0 e
17.8 f

64.2 b
30.3 c
0.0 e
25.1 f

50.9 b
34.6 c
0.0 e
14.1 f

0.0 e
28.6 f

63.4 b
26.9 c
0.0 e
16.0 f
 
62.6 b
24.3 c
0.0 e
22.5 f

67.3 b
30.8 c
0.0 e
27.3 f

0.0 e
24.9 f
 
67.3 b
30.8 c
0.0 e
27.3 f
mPW1PW91
16.7 b
-53.9 c
0.0 e
-114.9 f

62.5 b
6.2 c
0.0 e
14.6 f

67.7 b
11.2 c
0.0 e
14.5 f

65.1 b
27.5 c
0.0 e
42.4 f

46.9 b
25.2 c
0.0 e
4.0 f

58.6 b
23.7 c
0.0 e
16.1 f

61.0 b
27.6 c
0.0 e
23.7 f

46.8 b
31.6 c
0.0 e
11.8 f

0.0 e
26.6 f

64.3 b
28.6 c
0.0 e
14.2 f
 
58.5 b
21.4 c
0.0 e
21.0 f

68.3 b
32.2 c
0.0 e
25.2 f

0.0 e
22.9 f
 
68.3 b
32.2 c
0.0 e
25.2 f
PBEPBE
23.3 b
-79.6 c
0.0 e
-112.2 f

61.0 b
-13.0 c
0.0 e
3.7 f

61.0 b
-13.0 c
0.0 e
3.6 f

60.3 b
13.5 c
0.0 e
32.4 f

47.8 b
15.5 c
0.0 e
1.7 f

59.1 b
12.6 c
0.0 e
13.1 f

61.4 b
19.1 c
0.0 e
22.1 f

48.6 b
24.0 c
0.0 e
10.8 f

0.0 e
25.0 f

60.5 b
13.1 c
0.0 e
11.3 f

0.0 e
23.6 f

61.1 b
9.8 c
0.0 e
18.3 f

65.1 b
19.4 c
0.0 e
24.2 f

0.0 e
22.0 f
 
65.1 b
19.4 c
0.0 e
24.2 f
PBEPBEultrafine        
0.0 e
                     
Moller Plesset perturbation MP2
-27.8 b
13.2 c
0.0 e
-81.9 f

48.9 b
38.6 c
0.0 e
37.8 f

48.9 b
38.6 c
0.0 e
37.8 f

48.1 b
48.4 c
0.0 e
66.6 f

  b
  c

55.7 b
43.5 c
0.0 e
27.1 f

  b
  c

44.7 b
51.2 c
0.0 e
19.8 f

0.0 e
34.5 f

62.2 b
43.1 c
0.0 e
21.6 f
 
55.9 b
41.3 c
0.0 e
34.5 f

  b
  c

NC
NC
 
  b
  c
MP2=FULL
NC
NC

NC
NC

NC
NC

NC
NC

46.3 b
44.1 c
0.0 e
18.0 f

56.4 b
43.6 c
0.0 e
26.6 f

59.5 b
45.2 c
0.0 e
34.9 f

45.5 b
51.2 c
0.0 e
19.5 f

0.0 e
34.0 f

NC
NC
 
NC
NC

NC
NC
   
NC
NC
MP3        
0.0 e
25.9 f
                     
MP4  
NC
   
NC
NC
                     
Configuration interaction CID  
NC
NC

NC
NC

NC
NC

47.7 b
52.4 c
0.0 e
22.1 f
   
NC
NC
               
CISD  
NC
NC

NC
NC

NC
NC

47.2 b
52.0 c
0.0 e
21.6 f
   
NC
NC
               
Quadratic configuration interaction QCISD
NC
NC

NC
NC
NC

NC
NC

NC
NC

NC
NC

NC
NC
NC

NC
NC
NC

NC
NC

NC

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

NC
NC

NC
NC

NC
NC

NC
NC
NC

NC
NC

NC
NC

NC
NC
 
NC
NC
           
CCSD        
NC
NC
                     
CCSD(T)        
NC
NC
                     

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF
58.5 b
47.8 c
0.0 e
71.0 f

35.1 b
58.8 c
0.0 e
18.0 f

62.2 b
47.4 c
0.0 e
76.5 f

42.8 b
59.3 c
0.0 e
32.9 f

70.1 b
49.1 c
0.0 e
83.2 f

70.1 b
49.3 c
0.0 e
82.8 f
density functional B1B95
60.8 b
25.2 c
0.0 e
21.0 f

49.3 b
31.7 c
0.0 e
-14.3 f
       
B3LYP
56.9 b
26.5 c
0.0 e
37.0 f

44.3 b
32.4 c
0.0 e
7.1 f

58.5 b
24.7 c
0.0 e
45.6 f

48.8 b
32.7 c
0.0 e
21.6 f

65.0 b
24.2 c
0.0 e
45.8 f

64.8 b
24.6 c
0.0 e
45.8 f
Moller Plesset perturbation MP2
41.6 b
47.5 c
0.0 e
52.1 f

39.4 b
49.0 c
0.0 e
2.8 f

44.3 b
45.3 c
0.0 e
60.0 f

45.2 b
47.5 c
0.0 e
18.2 f

51.5 b
46.1 c
0.0 e
63.7 f

51.3 b
46.3 c
0.0 e
63.4 f

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 e
41.6 f

0.0 e
45.8 f
 
0.0 e
45.8 f
MP2FC// B3LYP/6-31G*  
0.0 e
34.1 f
     
MP2FC// MP2FC/6-31G*
0.0 e
32.4 f

0.0 e
35.8 f

0.0 e
33.9 f

0.0 e
38.0 f

0.0 e
33.9 f
MP4// HF/6-31G*  
0.0 e
43.7 f
     
MP4// MP2/6-31G*
0.0 e
33.2 f
       
Coupled Cluster CCSD// HF/6-31G*  
0.0 e
46.5 f

NC
 
NC
CCSD(T)// HF/6-31G*  
0.0 e
45.7 f

NC
 
NC
CCSD(T)//B3LYP/6-31G(2df,p)    
65.8 b
44.4 c
0.0 e
36.1 f
 
65.8 b
44.4 c
0.0 e
36.1 f
CCSD// MP2FC/6-31G*
0.0 e
36.0 f
 
0.0 e
38.8 f
 
0.0 e
38.8 f
CCSD(T)// MP2FC/6-31G*
0.0 e
35.9 f
 
0.0 e
38.3 f
 
0.0 e
38.3 f
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.