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

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

Isomers of C5H5NO

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C5H5NO 9000004 3(2H)-Pyridinone   sketch of 3(2H)-Pyridinone
b C5H5NO 9000015 3(6H)-Pyridinone   sketch of 3(6H)-Pyridinone
c C5H5NO 9000026 3(4H)-Pyridinone   sketch of 3(4H)-Pyridinone
d C5H5NO 9000037 2(5H)-Pyridinone   sketch of 2(5H)-Pyridinone
e C5H5NO 9000048 2(3H)-Pyridinone   sketch of 2(3H)-Pyridinone
f C5H5NO 9000059 4(3H)-Pryidinone   sketch of 4(3H)-Pryidinone
g C5H5NO 9000060 4(1H)-Pryidinone   sketch of 4(1H)-Pryidinone
h C5H5NO 72762006 2(1H)-Pyridinone   sketch of 2(1H)-Pyridinone
i C5H5NO 109104 2-Pyridinol   sketch of 2-Pyridinol
j C5H5NO 109002 3-Pyridinol 0.0 sketch of 3-Pyridinol
k C5H5NO 626642 4-Pyridinol 13.4 sketch of 4-Pyridinol
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM6 48.0 a
59.3 b
46.9 c
42.5 d
34.4 e
25.7 f
-6.4 g
-24.8 i
0.0 j
-14.6 k
composite G3B3 73.5 a
73.9 b
84.1 c
53.0 d
57.2 e
66.0 f
5.3 g
-33.7 h
-38.8 i
0.0 j
-9.4 k
G3MP2 77.4 a
78.2 b
86.0 c
56.3 d
58.5 e
67.5 f
13.3 g
-289.7 h
-33.4 i
0.0 j
-6.0 k
G4 73.0 a
73.7 b
83.5 c
52.5 d
55.6 e
65.2 f
4.9 g
-34.4 h
-38.9 i
0.0 j
-9.0 k

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 cc-pV(T+d)Z
hartree fock HF   90.1 a
89.7 b
97.9 c
68.7 d
74.0 e
81.2 f
-2.9 g
-47.3 h
-43.1 i
0.0 j
-9.6 k
                63.2 a
60.5 b
76.8 c
34.6 d
42.0 e
51.7 f
-4.5 g
-44.6 h
-47.6 i
0.0 j
-16.7 k
       
density functional LSDA 93.5 a
102.0 b
104.1 c
83.4 d
76.5 e
93.7 f
29.7 g
-21.2 h
-38.2 i
0.0 j
-5.3 k
83.9 a
84.4 b
90.3 c
66.0 d
66.1 e
75.9 f
-26.5 g
-69.9 h
-41.6 i
0.0 j
-5.6 k
83.9 a
84.4 b
90.3 c
66.0 d
66.1 e
75.9 f
-26.5 g
-69.9 h
-41.6 i
0.0 j
-5.6 k
84.3 a
87.1 b
95.8 c
72.7 d
72.3 e
78.5 f
-29.9 g
-71.4 h
-41.6 i
0.0 j
-6.1 k
82.0 a
83.2 b
93.0 c
65.3 d
64.2 e
73.6 f
-4.9 g
-48.6 h
-41.6 i
0.0 j
-7.9 k
92.7 a
93.9 b
103.1 c
75.5 d
74.2 e
83.9 f
-0.1 g
-43.6 h
-41.6 i
0.0 j
-7.9 k
92.7 a
94.4 b
103.8 c
76.4 d
74.8 e
83.3 f
-5.0 g
-46.1 h
-42.3 i
0.0 j
-8.3 k
78.3 a
79.1 b
89.0 c
60.6 d
59.1 e
69.1 f
-15.3 g
-59.1 h
-44.5 i
0.0 j
-8.5 k
94.1 a
95.0 b
104.3 c
76.1 d
74.3 e
84.6 f
-6.6 g
-49.9 h
-44.0 i
0.0 j
-8.4 k
97.9 a
97.5 b
107.6 c
78.2 d
77.5 e
88.3 f
-0.2 g
-43.1 h
-40.7 i
0.0 j
-8.0 k
  95.3 a
95.5 b
105.1 c
77.0 d
76.0 e
85.8 f
-2.2 g
-44.9 h
-41.7 i
0.0 j
-7.9 k
99.9 a
99.8 b
109.9 c
80.1 d
79.2 e
89.9 f
-3.9 g
-45.6 h
-42.2 i
0.0 j
-8.4 k
97.7 a
97.4 b
108.0 c
79.4 d
78.7 e
87.8 f
-3.6 g
-43.5 h
-40.8 i
0.0 j
-8.3 k
99.9 a
99.8 b
109.9 c
80.1 d
79.2 e
89.9 f
-3.9 g
-45.6 h
-42.2 i
0.0 j
-8.4 k
B1B95 82.5 a
89.4 b
91.1 c
72.0 d
68.3 e
82.2 f
45.8 g
0.2 h
-33.1 i
0.0 j
-5.6 k
77.1 a
77.6 b
84.6 c
59.9 d
62.5 e
70.4 f
-18.0 g
-60.2 h
-39.2 i
0.0 j
-6.4 k
77.1 a
77.6 b
84.6 c
59.9 d
62.5 e
70.3 f
-18.0 g
-60.2 h
-39.2 i
0.0 j
-6.4 k
79.9 a
82.9 b
92.3 c
68.8 d
70.6 e
74.8 f
-20.8 g
-61.0 h
-39.1 i
0.0 j
-6.7 k
  81.9 a
83.2 b
93.3 c
63.4 d
64.9 e
73.7 f
5.5 g
-37.5 h
-40.4 i
0.0 j
-9.2 k
82.8 a
84.5 b
94.9 c
65.0 d
66.2 e
73.9 f
1.4 g
-39.5 h
-40.9 i
0.0 j
-9.6 k
67.7 a
68.4 b
79.4 c
48.7 d
50.4 e
59.3 f
-7.7 g
-51.0 h
-42.5 i
0.0 j
-9.7 k
83.2 a
84.1 b
94.5 c
64.1 d
65.5 e
74.7 f
1.0 g
-41.7 h
-41.9 i
0.0 j
-9.5 k
86.6 a
86.1 b
97.3 c
65.2 d
67.7 e
77.8 f
5.7 g
-36.6 h
-39.7 i
0.0 j
-9.4 k
  84.0 a
83.9 b
94.9 c
64.0 d
66.3 e
75.5 f
3.9 g
-38.4 h
-40.5 i
0.0 j
-9.2 k
89.1 a
88.6 b
100.3 c
67.2 d
69.8 e
79.6 f
2.8 g
-38.4 h
-40.9 i
0.0 j
-9.8 k
87.3 a
86.6 b
98.8 c
69.3 e
77.8 f
3.4 g
-36.3 h
-39.6 i
0.0 j
-9.7 k
89.1 a
88.6 b
100.3 c
67.2 d
69.8 e
79.6 f
2.8 g
-38.4 h
-40.9 i
0.0 j
-9.8 k
B3LYP   71.7 a
72.1 b
80.1 c
56.6 d
59.8 e
66.3 f
-17.7 g
-59.4 h
-37.6 i
0.0 j
-6.1 k
    63.5 a
64.9 b
76.6 c
47.8 d
50.0 e
57.1 f
-1.3 g
-43.6 h
-39.1 i
0.0 j
-8.9 k
  76.1 a
77.8 b
89.3 c
60.7 d
62.5 e
68.5 f
-1.2 g
-41.1 h
-39.7 i
0.0 j
-9.3 k
               
Moller Plesset perturbation MP2   63.2 a
63.8 b
70.5 c
47.4 d
49.7 e
60.3 f
-8.0 g
-50.4 h
-36.4 i
0.0 j
-5.3 k
                         

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
density functional B1B95 76.3 a
80.3 b
89.2 c
70.3 d
71.8 e
69.8 f
-23.7 g
-59.2 h
-42.1 i
0.0 j
-11.6 k
69.4 a
72.3 b
80.7 c
52.0 d
53.0 e
58.6 f
1.0 g
-39.2 h
-40.7 i
0.0 j
-9.8 k
       
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.