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

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

Isomers of C6H6O

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C6H5OH 108952 phenol   sketch of phenol
b C6H6O 5664335 2,5-Cyclohexadienone   sketch of 2,5-Cyclohexadienone
c C6H6O 24599573 2,4-Cyclohexadienone   sketch of 2,4-Cyclohexadienone
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
composite G3MP2 0.0 a
70.6 b
76.1 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 cc-pV(T+d)Z
hartree fock HF   0.0 a
79.9 b
87.0 c
        0.0 a
57.5 b
65.0 c
      0.0 a
53.8 b
63.2 c
0.0 a
57.0 b
64.8 c
       
density functional LSDA 0.0 a
100.3 b
95.5 c
0.0 a
70.5 b
73.2 c
0.0 a
70.5 b
73.2 c
0.0 a
75.6 b
76.7 c
0.0 a
71.4 b
73.3 c
0.0 a
81.9 b
83.5 c
0.0 a
82.5 b
83.8 c
0.0 a
67.3 b
69.8 c
0.0 a
83.5 b
85.5 c
0.0 a
86.0 b
88.9 c
    0.0 a
83.8 b
86.4 c
0.0 a
88.7 b
91.4 c
0.0 a
86.5 b
89.2 c
0.0 a
88.7 b
91.4 c
B1B95             0.0 a
74.3 b
77.2 c
                 
B3LYP   0.0 a
62.2 b
66.3 c
    0.0 a
55.8 b
59.3 c
  0.0 a
68.7 b
71.7 c
        0.0 a
70.7 b
73.9 c
       
TPSSh             0.0 a
66.4 b
69.2 c
                 
Moller Plesset perturbation MP2                       0.0 a
97.1 b
97.7 c
       
MP3=FULL         0.0 a
55.7 b
61.2 c
 
NC
NC
                 
B2PLYP                           0.0 a
75.0 b
79.9 c
   

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
density functional B1B95 0.0 a
75.7 b
76.9 c
0.0 a
60.7 b
62.5 c
       
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.