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

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

Isomers of C4H5N

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C4H5N 9000366 3H-pyrrole   sketch of 3H-pyrrole
b C4H5N 9000377 2H-pyrrole   sketch of 2H-pyrrole
c C4H5N 109977 Pyrrole 0.0 sketch of Pyrrole
d C4H5N 1190767 (Z)-2-Butenenitrile 25.8 sketch of (Z)-2-Butenenitrile
e C4H5N 627269 (E)-2-Butenenitrile 32.5 sketch of (E)-2-Butenenitrile
f C4H5N 5500210 Cyclopropanecarbonitrile 74.5 sketch of Cyclopropanecarbonitrile
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1
0.0 c
-20.0 d
-22.1 e
37.4 f
PM3
0.0 c
48.4 d
45.4 e
103.2 f
PM6
0.0 c
31.2 d
29.8 e
68.7 f
MNDOd
0.0 c
7.4 d
5.3 e
44.3 f
composite G1
0.0 c
G2MP2
0.0 c
G2
0.0 c
G3
0.0 c
8.1 d
7.4 e
60.4 f
G3B3 -153.0 a
-159.8 b
0.0 c
25.8 d
26.3 e
69.6 f
G3MP2
0.0 c
9.5 d
9.2 e
63.8 f
G4
0.0 c
29.4 d
30.1 e
71.2 f
CBS-Q
0.0 c
30.2 d
30.5 e
72.3 f
Group additivity gaw
150.0 d
molecular mechanics MM3
0.0 c
-323.3 d
-324.8 e
91.0 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
0.0 c
29.4 d
28.5 e
30.9 f

0.0 c
-0.6 d
-0.7 e
61.9 f

0.0 c
-0.6 d
-0.7 e
61.9 f

0.0 c
19.1 d
18.6 e
81.5 f
 
0.0 c
-1.8 d
-2.6 e
39.0 f
 
0.0 c
-12.6 d
-13.6 e
32.6 f

0.0 c
-4.0 d
-4.8 e
40.7 f

0.0 c
-5.3 d
-6.1 e
37.2 f

0.0 c
2.3 d
1.5 e
47.1 f

0.0 c
-0.0 d
-0.9 e
45.5 f

0.0 c
0.2 d
-0.6 e
46.2 f

0.0 c
5.6 d
4.8 e
50.0 f

0.0 c
2.5 d
1.7 e
48.6 f

0.0 c
0.2 d
-0.6 e
46.2 f
density functional LSDA
0.0 c
143.2 d
145.0 e
146.0 f

0.0 c
98.7 d
102.5 e
139.1 f

0.0 c
98.7 d
102.5 e
139.1 f

0.0 c
115.3 d
117.7 e
154.0 f

0.0 c
109.1 d
111.8 e
129.7 f

0.0 c
115.7 d
118.5 e
136.7 f

0.0 c
120.9 d
123.5 e
141.4 f

0.0 c
103.5 d
106.2 e
127.2 f

0.0 c
112.5 d
115.5 e
135.9 f

0.0 c
121.6 d
124.5 e
142.1 f
 
0.0 c
124.5 d
127.5 e
147.0 f

0.0 c
118.8 d
121.7 e
141.8 f

0.0 c
128.7 d
131.3 e
148.0 f
 
0.0 c
118.8 d
121.7 e
141.8 f
BLYP
0.0 c
45.4 d
45.2 e
78.4 f

0.0 c
8.9 d
9.3 e
78.4 f

0.0 c
8.9 d
9.3 e
78.4 f

0.0 c
23.6 d
23.4 e
93.2 f

0.0 c
14.3 d
14.2 e
68.4 f

0.0 c
21.4 d
21.3 e
75.4 f

0.0 c
27.5 d
27.1 e
81.6 f

0.0 c
10.2 d
10.0 e
67.6 f

0.0 c
19.0 d
19.0 e
75.7 f

0.0 c
24.3 d
24.2 e
78.5 f
 
0.0 c
31.3 d
31.2 e
86.9 f
 
0.0 c
34.7 d
34.2 e
86.5 f
   
B1B95
0.0 c
78.5 d
78.5 e
84.8 f

0.0 c
45.1 d
47.3 e
89.8 f

0.0 c
45.1 d
47.3 e
89.8 f

0.0 c
62.1 d
62.9 e
105.7 f

0.0 c
51.6 d
52.3 e
75.2 f

0.0 c
57.8 d
58.6 e
82.6 f

0.0 c
63.3 d
64.1 e
88.3 f

0.0 c
47.3 d
48.1 e
75.4 f

0.0 c
56.1 d
57.2 e
83.6 f

0.0 c
61.5 d
62.3 e
86.0 f
 
0.0 c
64.7 d
65.8 e
91.7 f

0.0 c
63.2 d
64.1 e
89.3 f

0.0 c
70.0 d
70.7 e
93.4 f
 
0.0 c
63.2 d
64.1 e
89.3 f
B3LYP
0.0 c
60.5 d
60.4 e
82.2 f

0.0 c
22.5 d
23.3 e
84.6 f

0.0 c
22.5 d
23.3 e
84.6 f

0.0 c
39.4 d
39.4 e
101.3 f

0.0 c
26.9 d
27.0 e
71.7 f

0.0 c
34.3 d
34.5 e
79.1 f

  d
  e
  f

0.0 c
23.0 d
23.0 e
71.5 f

0.0 c
31.9 d
32.1 e
79.8 f

0.0 c
36.2 d
36.4 e
81.7 f

0.0 c
38.3 d
38.4 e
85.5 f

0.0 c
42.4 d
42.6 e
89.4 f

0.0 c
35.6 d
35.7 e
83.9 f

0.0 c
46.7 d
46.5 e
90.9 f
 
0.0 c
35.6 d
35.7 e
83.9 f
B3LYPultrafine        
0.0 c
27.0 d
27.1 e
71.7 f
                     
B3PW91
0.0 c
74.4 d
74.1 e
85.8 f

0.0 c
44.4 d
45.5 e
92.5 f

0.0 c
44.4 d
45.5 e
92.5 f

0.0 c
60.2 d
60.4 e
108.3 f

0.0 c
49.1 d
49.4 e
79.0 f

0.0 c
56.6 d
56.9 e
86.5 f

0.0 c
62.5 d
62.7 e
92.5 f

0.0 c
46.2 d
46.4 e
79.6 f

0.0 c
55.2 d
55.7 e
88.1 f

0.0 c
58.9 d
59.2 e
89.5 f
 
0.0 c
63.2 d
63.6 e
95.5 f

0.0 c
59.3 d
59.6 e
92.4 f

0.0 c
67.2 d
67.3 e
97.2 f
 
0.0 c
59.3 d
59.6 e
92.4 f
mPW1PW91
0.0 c
79.9 d
79.8 e
87.5 f

0.0 c
50.6 d
52.1 e
95.6 f

0.0 c
50.7 d
52.2 e
95.6 f

0.0 c
66.5 d
67.0 e
111.4 f

0.0 c
54.4 d
55.0 e
80.9 f

0.0 c
62.0 d
62.7 e
88.6 f

0.0 c
68.2 d
68.7 e
94.9 f

0.0 c
51.4 d
52.0 e
81.6 f

0.0 c
60.2 d
61.0 e
89.9 f

0.0 c
63.8 d
64.3 e
91.1 f
 
0.0 c
68.2 d
68.9 e
97.5 f

0.0 c
64.3 d
64.9 e
94.3 f

0.0 c
71.8 d
72.2 e
98.8 f
 
0.0 c
64.3 d
64.9 e
94.3 f
PBEPBE
0.0 c
73.5 d
73.7 e
90.8 f

0.0 c
43.0 d
44.5 e
93.1 f

0.0 c
43.0 d
44.5 e
93.1 f

0.0 c
55.9 d
56.5 e
106.7 f

0.0 c
48.9 d
49.6 e
82.2 f

0.0 c
56.3 d
57.1 e
89.6 f

0.0 c
61.8 d
62.3 e
95.0 f

0.0 c
46.3 d
47.0 e
82.6 f

0.0 c
55.4 d
56.3 e
91.1 f

0.0 c
59.9 d
60.6 e
93.1 f

0.0 c
62.0 d
62.7 e
96.4 f

0.0 c
64.6 d
65.4 e
99.8 f

0.0 c
59.9 d
60.6 e
95.6 f

0.0 c
68.2 d
68.7 e
100.2 f
 
0.0 c
59.9 d
60.6 e
95.6 f
PBEPBEultrafine        
  d
  e
                     
Moller Plesset perturbation MP2
0.0 c
-73.9 d
-74.2 e
-38.6 f

0.0 c
-36.6 d
-35.8 e
27.9 f

0.0 c
-36.6 d
-35.8 e
27.9 f

0.0 c
-22.3 d
-22.6 e
39.9 f
 
0.0 c
26.7 d
27.3 e
55.6 f
 
0.0 c
25.7 e
54.2 f

0.0 c
30.7 d
31.8 e
59.5 f

0.0 c
42.4 d
44.5 e
69.0 f
 
0.0 c
32.5 d
202.5 e
65.3 f

  f
   
  d
  e
  f
MP2=FULL        
0.0 c
22.7 d
23.4 e
51.1 f

0.0 c
27.8 d
28.5 e
55.9 f

0.0 c
38.7 d
39.3 e
67.0 f

0.0 c
26.3 d
27.5 e
54.8 f

0.0 c
32.6 d
33.7 e
60.1 f
             
MP3        
0.0 c
23.6 d
23.6 e
56.8 f
                     
Configuration interaction CID        
0.0 c
18.2 d
18.0 e
48.5 f
                     
CISD        
0.0 c
16.4 d
16.2 e
47.5 f
                     
Quadratic configuration interaction QCISD  
0.0 c
-29.7 d
-29.3 e
40.9 f
     
0.0 c
46.6 f

0.0 c
56.1 f
 
0.0 c
47.0 f
             
Coupled Cluster CCD        
NC
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 c
38.8 d
36.5 e
90.7 f

0.0 c
7.4 d
4.9 e
38.8 f

0.0 c
32.5 d
32.0 e
90.0 f

0.0 c
-6.6 d
-7.5 e
35.9 f

0.0 c
33.1 d
32.7 e
95.7 f

0.0 c
33.0 d
32.6 e
95.3 f
density functional B1B95
0.0 c
92.1 d
90.9 e
118.8 f

0.0 c
78.7 d
77.5 e
87.3 f
       
B3LYP
0.0 c
59.0 d
57.2 e
108.8 f

0.0 c
42.3 d
40.7 e
76.9 f

0.0 c
53.9 d
54.1 e
111.8 f

0.0 c
30.2 d
30.3 e
75.7 f

0.0 c
58.2 d
58.4 e
117.6 f

0.0 c
58.0 d
58.1 e
117.3 f
Moller Plesset perturbation MP2
0.0 c
-8.4 d
-10.8 e
42.2 f

0.0 c
30.3 d
29.2 e
49.1 f

0.0 c
-5.0 d
-5.1 e
48.7 f

0.0 c
29.0 d
30.0 e
56.5 f

0.0 c
-12.4 d
-11.5 e
48.6 f

0.0 c
-12.9 d
-12.0 e
48.0 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 c
24.1 d
23.7 e
63.2 f

0.0 c
35.3 d
154.0 e
154.7 f
 
0.0 c
35.3 d
154.0 e
154.7 f
MP2FC// B3LYP/6-31G*  
0.0 c
35.9 d
37.1 e
68.1 f
     
MP2FC// MP2FC/6-31G*
0.0 c
55.3 d
84.3 f

0.0 c
34.2 d
67.9 f

0.0 c
49.9 d
52.2 e
80.7 f

0.0 c
44.9 d
46.6 e
78.1 f

0.0 c
49.9 d
52.2 e
80.7 f
MP4// HF/6-31G*  
0.0 c
-0.4 d
-1.4 e
45.6 f
     
MP4// MP2/6-31G*
0.0 c
31.5 d
66.3 f
       
Coupled Cluster CCSD// HF/6-31G*  
0.0 c
0.5 d
-0.7 e
47.5 f

0.0 c
9.7 d
 
0.0 c
9.7 d
CCSD(T)// HF/6-31G*  
0.0 c
3.2 d
2.3 e
52.8 f

0.0 c
14.6 d
 
0.0 c
14.6 d
CCSD(T)//B3LYP/6-31G(2df,p)    
0.0 c
69.7 f
 
0.0 c
69.7 f
CCSD// MP2FC/6-31G*
0.0 c
35.5 d
71.1 f

0.0 c

0.0 c
30.8 d
31.9 e
68.7 f
 
0.0 c
30.8 d
31.9 e
68.7 f
CCSD(T)// MP2FC/6-31G*
0.0 c
37.6 d
76.1 f

0.0 c

0.0 c
32.7 d
34.1 e
73.4 f
 
0.0 c
32.7 d
34.1 e
73.4 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.