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

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

Isomers of C5H12

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C5H12 78784 Butane, 2-methyl- 15.3 sketch of Butane, 2-methyl-
b C5H12 109660 Pentane 20.1 sketch of Pentane
c C5H12 463821 Propane, 2,2-dimethyl- 0.0 sketch of Propane, 2,2-dimethyl-
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
composite G3 17.6 a
24.1 b
0.0 c
G3B3
21.3 b
0.0 c
G3MP2 17.3 a
24.0 b
0.0 c
CBS-Q 18.5 a
22.7 b
0.0 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 aug-cc-pVTZ cc-pV(T+d)Z
hartree fock HF 5.9 a
3.1 b
0.0 c
14.1 a
16.2 b
0.0 c
14.1 a
16.2 b
0.0 c
8.4 a
7.0 b
0.0 c
  7.4 a
5.0 b
0.0 c
7.9 a
5.7 b
0.0 c
8.0 a
5.6 b
0.0 c
7.8 a
5.6 b
0.0 c
7.0 a
4.3 b
0.0 c
7.4 a
5.0 b
0.0 c
7.6 a
5.2 b
0.0 c
7.4 a
4.8 b
0.0 c
7.0 a
4.1 b
0.0 c
7.5 a
5.0 b
0.0 c
6.9 a
4.0 b
0.0 c
7.0 a
4.1 b
0.0 c
density functional LSDA 7.6 a
11.7 b
0.0 c
14.3 a
25.6 b
0.0 c
14.3 a
25.6 b
0.0 c
10.6 a
18.4 b
0.0 c
10.1 a
17.4 b
0.0 c
10.1 a
17.6 b
0.0 c
11.1 a
18.6 b
0.0 c
11.1 a
19.0 b
0.0 c
11.5 a
20.0 b
0.0 c
11.2 a
19.3 b
0.0 c
    9.9 a
17.4 b
0.0 c
10.2 a
18.0 b
0.0 c
11.0 a
19.8 b
0.0 c
  10.2 a
18.0 b
0.0 c
SVWN   14.2 a
25.6 b
0.0 c
    10.1 a
17.4 b
0.0 c
  11.1 a
18.6 b
0.0 c
                   
BLYP 3.4 a
2.2 b
0.0 c
7.2 a
8.8 b
0.0 c
7.1 a
8.8 b
0.0 c
4.7 a
4.3 b
0.0 c
  4.2 a
3.4 b
0.0 c
4.9 a
4.0 b
0.0 c
NC
NC
4.5 a
3.6 b
0.0 c
5.2 a
4.9 b
0.0 c
    4.0 a
3.1 b
0.0 c
3.6 a
2.4 b
0.0 c
5.0 a
4.6 b
0.0 c
  3.6 a
2.4 b
0.0 c
B1B95 5.2 a
4.3 b
0.0 c
12.9 a
18.6 b
0.0 c
12.9 a
18.6 b
0.0 c
7.4 a
9.2 b
0.0 c
6.7 a
7.9 b
0.0 c
6.7 a
8.0 b
0.0 c
7.3 a
8.9 b
0.0 c
7.6 a
9.3 b
0.0 c
7.9 a
9.7 b
0.0 c
6.8 a
8.2 b
0.0 c
    6.5 a
7.2 b
0.0 c
7.1 a
8.3 b
0.0 c
7.2 a
8.9 b
0.0 c
  7.1 a
8.3 b
0.0 c
B3LYP 4.5 a
3.6 b
0.0 c
9.4 a
12.2 b
0.0 c
9.4 a
12.2 b
0.0 c
6.0 a
6.1 b
0.0 c
5.4 a
4.8 b
0.0 c
5.4 a
5.1 b
0.0 c
6.1 a
5.8 b
0.0 c
5.8 a
5.2 b
0.0 c
6.0 a
5.9 b
0.0 c
6.2 a
6.1 b
0.0 c
6.1 a
6.0 b
0.0 c
5.9 a
5.5 b
0.0 c
5.2 a
4.8 b
0.0 c
5.1 a
4.5 b
0.0 c
6.2 a
6.3 b
0.0 c
  5.1 a
4.5 b
0.0 c
B3LYPultrafine         7.0 a
6.3 b
0.0 c
                       
B3PW91 4.4 a
2.7 b
0.0 c
10.7 a
14.3 b
0.0 c
10.7 a
14.3 b
0.0 c
6.2 a
6.3 b
0.0 c
  5.6 a
5.3 b
0.0 c
6.2 a
6.1 b
0.0 c
6.4 a
6.2 b
0.0 c
6.5 a
6.8 b
0.0 c
5.9 a
5.7 b
0.0 c
    5.3 a
4.9 b
0.0 c
5.2 a
4.8 b
0.0 c
6.0 a
6.1 b
0.0 c
  5.2 a
4.8 b
0.0 c
mPW1PW91 5.0 a
4.1 b
0.0 c
12.0 a
16.8 b
0.0 c
11.9 a
16.5 b
0.0 c
7.0 a
7.9 b
0.0 c
6.4 a
6.8 b
0.0 c
6.5 a
7.1 b
0.0 c
7.2 a
8.0 b
0.0 c
7.4 a
8.0 b
0.0 c
7.4 a
8.4 b
0.0 c
6.5 a
7.0 b
0.0 c
    6.3 a
6.7 b
0.0 c
6.0 a
6.2 b
0.0 c
6.8 a
7.5 b
0.0 c
  6.0 a
6.2 b
0.0 c
M06-2X         9.7 a
15.5 b
0.0 c
                       
PBEPBE 4.5 a
4.4 b
0.0 c
10.3 a
15.1 b
0.0 c
10.3 a
15.1 b
0.0 c
6.3 a
8.0 b
0.0 c
5.7 a
6.8 b
0.0 c
5.8 a
7.1 b
0.0 c
6.6 a
8.0 b
0.0 c
6.4 a
7.5 b
0.0 c
6.7 a
8.5 b
0.0 c
6.2 a
7.8 b
0.0 c
6.7 a
8.5 b
0.0 c
  5.5 a
6.8 b
0.0 c
5.6 a
6.8 b
0.0 c
6.3 a
8.1 b
0.0 c
  5.6 a
6.8 b
0.0 c
PBEPBEultrafine         7.8 a
8.6 b
0.0 c
                       
PBE1PBE         7.0 a
8.1 b
0.0 c
                       
HSEh1PBE         7.0 a
8.1 b
0.0 c
                       
TPSSh             6.1 a
6.6 b
0.0 c
                   
Moller Plesset perturbation MP2 9.3 a
9.4 b
0.0 c
19.9 a
27.3 b
0.0 c
19.9 a
27.3 b
0.0 c
16.4 a
21.3 b
0.0 c
  16.6 a
21.9 b
0.0 c

24.6 b
0.0 c
19.8 a
26.6 b
0.0 c
18.8 a
25.7 b
0.0 c
17.9 a
25.0 b
0.0 c
  19.6 a
27.1 b
0.0 c
17.2 a
23.2 b
0.0 c
       
MP2=FULL           17.1 a
22.7 b
0.0 c
18.7 a
25.4 b
0.0 c
  19.1 a
26.3 b
0.0 c
               
MP3         13.7 a
16.9 b
0.0 c
                       
MP3=FULL         14.2 a
17.6 b
0.0 c
  15.1 a
19.3 b
0.0 c
                   
B2PLYP         9.8 a
11.4 b
0.0 c
                9.8 a
11.9 b
0.0 c
     
Quadratic configuration interaction QCISD   17.8 a
23.8 b
0.0 c
     
16.2 b
0.0 c

18.4 b
0.0 c
 
19.3 b
0.0 c
               

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 9.8 a
9.4 b
0.0 c
10.2 a
9.7 b
0.0 c
8.7 a
7.0 b
0.0 c
9.0 a
7.0 b
0.0 c
8.3 a
6.8 b
0.0 c
8.5 a
7.0 b
0.0 c
density functional B1B95 7.8 a
10.5 b
0.0 c
8.8 a
11.8 b
0.0 c
       
B3LYP 7.8 a
9.4 b
0.0 c
8.5 a
10.3 b
0.0 c
6.5 a
6.7 b
0.0 c
7.0 a
7.2 b
0.0 c
6.3 a
7.1 b
0.0 c
6.3 a
7.1 b
0.0 c
Moller Plesset perturbation MP2 19.1 a
26.5 b
0.0 c
20.7 a
28.5 b
0.0 c
20.9 a
29.0 b
0.0 c
22.9 a
31.3 b
0.0 c
18.1 a
25.8 b
0.0 c
18.3 a
26.2 b
0.0 c

Single point energy calculations (select basis sets)
cc-pVDZ cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2FC// HF/6-31G* 16.7 a
22.1 b
0.0 c
   
MP2FC// B3LYP/6-31G* 14.7 a
20.5 b
0.0 c
   
MP4// HF/6-31G* 13.6 a
16.9 b
0.0 c
   
Coupled Cluster CCSD// HF/6-31G* 13.3 a
16.3 b
0.0 c
   
CCSD(T)// HF/6-31G* 14.7 a
18.7 b
0.0 c
   
CCSD(T)//B3LYP/6-31G(2df,p)  
17.4 b
0.0 c

17.4 b
0.0 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.