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

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

Isomers of C3H5NO

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH2CHCONH2 79061 Acrylamide 0.0 sketch of Acrylamide
b CH3OCH2CN 1738369 Methoxyacetonitrile 94.5 sketch of Methoxyacetonitrile
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1 0.0 a
31.0 b
PM3 0.0 a
65.7 b
PM6 0.0 a
68.4 b
MNDOd 0.0 a
28.1 b
composite G1
NC
G2MP2
NC
G2
NC
G3 0.0 a
94.0 b
G3B3 0.0 a
94.5 b
G3MP2 0.0 a
94.7 b
G4 0.0 a
88.9 b
CBS-Q 0.0 a
97.7 b
molecular mechanics MM3 0.0 a
397.1 b

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 a
-98.7 b
0.0 a
58.8 b
0.0 a
58.8 b
0.0 a
106.3 b
  0.0 a
81.0 b
  0.0 a
70.2 b
0.0 a
81.4 b
0.0 a
74.9 b
0.0 a
83.2 b
0.0 a
86.7 b
0.0 a
82.6 b
0.0 a
87.4 b
0.0 a
83.4 b
0.0 a
82.6 b
density functional LSDA 0.0 a
3.4 b
0.0 a
117.8 b
0.0 a
117.8 b
0.0 a
152.9 b
0.0 a
115.1 b
0.0 a
126.9 b
0.0 a
137.7 b
0.0 a
123.6 b
0.0 a
135.8 b
0.0 a
126.2 b
  0.0 a
130.6 b
0.0 a
135.2 b
0.0 a
140.6 b
  0.0 a
135.2 b
BLYP 0.0 a
-29.2 b
0.0 a
71.8 b
0.0 a
71.8 b
0.0 a
109.7 b
0.0 a
79.9 b
0.0 a
91.6 b
0.0 a
104.3 b
0.0 a
89.5 b
0.0 a
100.5 b
0.0 a
96.6 b
  0.0 a
96.5 b

  b
0.0 a
112.8 b
 
  b
B1B95 0.0 a
-31.2 b
0.0 a
93.6 b
0.0 a
93.6 b
0.0 a
129.2 b
0.0 a
93.1 b
0.0 a
105.7 b
0.0 a
108.3 b
0.0 a
99.2 b
0.0 a
111.0 b
0.0 a
103.5 b
  0.0 a
108.4 b
0.0 a
109.5 b
0.0 a
115.8 b
  0.0 a
109.5 b
B3LYP 0.0 a
-37.4 b
0.0 a
75.7 b
0.0 a
75.7 b
0.0 a
115.6 b
0.0 a
81.8 b
0.0 a
94.6 b
0.0 a
106.1 b
0.0 a
90.4 b
0.0 a
101.9 b
0.0 a
98.8 b
0.0 a
108.7 b
0.0 a
98.3 b

  b
0.0 a
109.4 b
 
  b
B3LYPultrafine         0.0 a
82.3 b
                     
B3PW91 0.0 a
-28.8 b
0.0 a
88.4 b
0.0 a
88.4 b
0.0 a
125.4 b
0.0 a
91.5 b
0.0 a
104.2 b
0.0 a
113.1 b
0.0 a
98.3 b
0.0 a
110.1 b
0.0 a
107.9 b
  0.0 a
106.0 b
0.0 a
109.3 b
0.0 a
119.2 b
  0.0 a
109.3 b
mPW1PW91 0.0 a
-30.9 b
0.0 a
84.1 b
0.0 a
89.0 b
0.0 a
134.4 b
0.0 a
87.5 b
0.0 a
100.3 b
0.0 a
109.6 b
0.0 a
93.8 b
0.0 a
110.4 b
0.0 a
108.5 b
  0.0 a
102.0 b
0.0 a
109.8 b
0.0 a
119.7 b
  0.0 a
109.8 b
PBEPBE 0.0 a
-14.6 b
0.0 a
99.5 b
0.0 a
88.1 b
0.0 a
125.1 b
0.0 a
93.7 b
0.0 a
106.0 b
0.0 a
117.0 b
0.0 a
102.0 b
0.0 a
113.8 b
0.0 a
110.8 b
0.0 a
120.7 b
0.0 a
109.4 b
0.0 a
118.8 b
0.0 a
124.4 b
  0.0 a
118.8 b
PBEPBEultrafine        
  b
                     
Moller Plesset perturbation MP2 0.0 a
-145.4 b
0.0 a
23.7 b
0.0 a
23.7 b
0.0 a
63.3 b
  0.0 a
65.4 b

  b
0.0 a
66.0 b
0.0 a
72.2 b

  b
  0.0 a
70.5 b
0.0 a
NC
  0.0 a
79.6 b
MP2=FULL
NC

NC

NC

NC
0.0 a
57.8 b
0.0 a
65.7 b
0.0 a
77.4 b
0.0 a
66.9 b
0.0 a
73.1 b
   
NC
     
NC
MP3         0.0 a
68.9 b
                     
Configuration interaction CID  
NC
    0.0 a
68.3 b
                     
CISD  
NC
    0.0 a
68.5 b
                     
Quadratic configuration interaction QCISD   0.0 a
40.0 b

NC

NC

NC
0.0 a
71.9 b

NC

NC

NC
             
Coupled Cluster CCD  
NC

NC

NC
0.0 a
60.8 b

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 a
97.1 b
0.0 a
62.4 b
0.0 a
98.6 b
0.0 a
62.8 b
0.0 a
104.3 b
0.0 a
104.4 b
density functional B1B95 0.0 a
120.5 b
0.0 a
90.3 b
       
B3LYP 0.0 a
108.4 b
0.0 a
80.8 b
0.0 a
110.5 b
0.0 a
82.1 b
0.0 a
118.0 b
0.0 a
118.3 b
Moller Plesset perturbation MP2 0.0 a
51.7 b
0.0 a
52.9 b
0.0 a
55.3 b
0.0 a
57.9 b
0.0 a
57.6 b
0.0 a
57.4 b

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 a
91.1 b
0.0 a
94.3 b
  0.0 a
94.3 b
MP2FC// B3LYP/6-31G*   0.0 a
80.8 b
     
MP2FC// MP2FC/6-31G*
NC

NC

NC
0.0 a
88.2 b

NC
MP4// HF/6-31G*   0.0 a
87.5 b
     
MP4// MP2/6-31G*
NC
       
Coupled Cluster CCSD// HF/6-31G*   0.0 a
87.5 b

NC
 
NC
CCSD(T)// HF/6-31G*   0.0 a
90.6 b

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