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

Isomers of C6H12

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C6H12 2398096 cis-1,3-dimethylcyclobutane   sketch of cis-1,3-dimethylcyclobutane
b C6H12 2398109 (1r,3r)-1,3-dimethylcyclobutane   sketch of (1r,3r)-1,3-dimethylcyclobutane
c C6H12 7642093 (Z)-hex-3-ene   sketch of (Z)-hex-3-ene
d C6H12 7688213 (Z)-hex-2-ene   sketch of (Z)-hex-2-ene
e C6H12 13269528 (E)-hex-3-ene   sketch of (E)-hex-3-ene
f C6H12 15679013 cis-1,2-dimethylcyclobutane   sketch of cis-1,2-dimethylcyclobutane
g C6H12 15679024 (1R,2R)-1,2-dimethylcyclobutane   sketch of (1R,2R)-1,2-dimethylcyclobutane
h C4H6(CH3)2 18931710 dimethylcyclobutane   sketch of dimethylcyclobutane
i C6H12 110827 Cyclohexane 0.0 sketch of Cyclohexane
j C6H12 96377 Cyclopentane, methyl- 16.4 sketch of Cyclopentane, methyl-
k C6H12 563791 2,3-dimethyl-but-2-ene 52.8 sketch of 2,3-dimethyl-but-2-ene
l C6H12 563780 2,3-dimethylbut-1-ene 57.3 sketch of 2,3-dimethylbut-1-ene
m C6H12 616126 (E)-3-methylpent-2-ene 59.6 sketch of (E)-3-methylpent-2-ene
n C6H12 922623 (Z)-3-methylpent-2-ene 61.3 sketch of (Z)-3-methylpent-2-ene
o C6H12 760214 3-methylenepentane 67.1 sketch of 3-methylenepentane
p C6H12 4050457 (E)-2-Hexene 72.1 sketch of (E)-2-Hexene
q C6H12 592416 hex-1-ene 81.0 sketch of hex-1-ene
r C6H12 4806615 Ethylcyclobutane 95.4 sketch of Ethylcyclobutane
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1
68.5 c
67.7 d
0.0 i
-425.0 j
-350.6 k
88.8 l
-347.7 m
-348.0 n
-334.7 o
78.1 q
-338.6 r
PM3
50.2 c
38.5 h
0.0 i
52.9 l
64.5 q
PM6 18.0 a
421.1 b
38.5 c
35.4 d
24.1 f
18.6 g
12.9 h
0.0 i
-15.5 j
-2.4 k
26.0 l
16.4 m
16.2 n
33.5 o
829.5 p
51.3 q
31.0 r
MNDOd
0.0 i
8.0 j
90.6 k
83.5 m
99.3 o
111.1 q
57.3 r
composite G1
40.5 b
-442.3 c
19.3 d
-434.8 h
0.0 i
-493.4 j
-464.6 k
-460.9 l
-458.5 n
-451.8 o
-440.2 q
G2MP2
39.4 b
-440.6 c
21.0 d
-436.0 h
0.0 i
-493.2 j
-462.7 k
-459.5 l
-457.0 n
-450.1 o
-438.6 q
G2
39.4 b
-440.8 c
20.7 d
-436.0 h
0.0 i
-493.4 j
-462.8 k
-459.7 l
-457.2 n
478.3 p
-438.8 q
G3
41.4 b
-441.0 c
20.4 d
-433.9 h
0.0 i
-492.5 j
-463.5 k
-459.1 l
-456.6 m
-457.2 n
478.1 p
-438.7 q
-414.4 r
G3B3 -840.7 a
45.2 b
-411.1 c
-413.6 d
-829.5 f
-841.5 g
-404.0 h
0.0 i
-463.0 j
-432.9 k
-429.2 l
-426.9 m
-427.0 n
13.9 p
-409.6 q
-384.5 r
G3MP2
-433.5 h
0.0 i
-492.4 j
-464.9 k
-458.4 m
-458.8 n
-451.3 o
-439.5 q
-414.4 r
G4
40.9 b
-408.0 c
-410.7 d
-402.2 h
0.0 i
-459.9 j
-431.4 k
-427.3 l
-424.9 m
-424.7 n
15.7 p
-406.3 q
-382.5 r
CBS-Q
46.1 b
35.2 c
29.7 d
42.8 h
0.0 i
19.3 l
21.2 p
37.1 q
molecular mechanics MM3
0.0 i
55.2 k
63.0 m
62.6 n
80.9 q
99.9 r

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
  j
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  j
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  r

  j
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  r

  j
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  r

0.0 i
18.0 j
58.5 k
54.6 m
54.6 n
98.4 r

  j
  k
  m
  n
  r

  j
  k
  m
  n
  r

  j
  m
  n
  r

  j
  k
  m
  n
  r

0.0 i
-454.7 j
-414.2 k
-417.9 m
-417.8 n
-413.0 o
-373.8 r
density functional LSDA
  j
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  j
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  j
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  j
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  j
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  j
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  j
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  j
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  j
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  j
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  r

  j
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  j
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  r
 
0.0 i
-411.8 j
-359.9 k
-347.8 m
-346.4 n
-334.3 o
-321.0 q
-327.6 r
BLYP
  j
  k
  m
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  j
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  k

  j
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  j
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  k

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  j
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  j
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  r

0.0 i
14.9 j
39.5 k
41.7 m
42.1 n
88.2 r
 
0.0 i
-419.2 j
-406.2 k
-404.3 m
-403.7 n
-393.7 o
-385.3 q
-346.8 r
B1B95
  j
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  j
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  j
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  j
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  j
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  j
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  j
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  r
 
0.0 i
-432.6 j
-392.1 k
-384.7 m
-384.0 n
-374.8 o
-365.5 q
-356.7 r
B3LYP
  j
  k
  m
  n
  r

  j
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  j
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  j
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  j
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  j
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  j
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  j
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  n
  o
  r

  j
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  n
  r

0.0 i
15.6 j
41.6 k
43.7 m
44.2 n
92.0 r

  j
  k
  m
  r

  j
  k
  m
  n
  r

  j
  m
  o
  r
 
0.0 i
-429.5 j
-403.5 k
-401.5 m
-400.9 n
-391.4 o
-383.3 q
-352.8 r
B3LYPultrafine        
  j
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  m
  n
  r
                     
B3PW91
  j
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  n
  o
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  j
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  j
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  m
  n
  r

  j
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  j
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  j
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  j
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  j
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  j
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  n
  o
  r

  j
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  n
  r
 
  j
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  r

  j
  k
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  n
  r

0.0 i
16.4 j
66.9 k
70.4 m
71.0 n
95.3 r
 
0.0 i
-430.5 j
-389.0 k
-385.4 m
-384.8 n
-373.9 o
-365.7 q
-352.3 r
mPW1PW91
  j
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  j
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  j
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  r
 
  j
  k
  m
  n

  j
  k
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  n
  o
  r

0.0 i
17.1 j
72.6 k
76.4 m
76.9 n
97.3 r
 
0.0 i
-432.3 j
-385.7 k
-381.7 m
-381.1 n
-370.6 o
-362.1 q
-352.7 r
PBEPBE
  j
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  j
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  j
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0.0 i
14.8 j
50.2 k
55.4 m
56.0 n
89.9 r

  j
  k
  m
  r

  j
  k
  m
  n
  r

0.0 i
15.9 j
60.2 k
65.4 m
66.0 n
76.2 o
91.9 r
 
0.0 i
-418.6 j
-383.2 k
-378.0 m
-377.3 n
-365.4 o
-356.2 q
-342.9 r
PBEPBEultrafine        
  j
  n
  r
                     
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
Moller Plesset perturbation MP2
  j
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MP2=FULL        
  j
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  k
 
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  j
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  o
  r
             
MP3        
  j
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  n
  r
                     
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

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF
  j
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density functional B1B95
0.0 i
10.6 j
72.9 k
76.6 m
76.3 n
85.0 r

0.0 i
12.1 j
85.4 k
88.7 m
88.0 n
84.7 r
       
B3LYP
  j
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  m
  n
  r

  j
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  k
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  k
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Moller Plesset perturbation MP2
  j
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  j
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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 i
-2689.1 j
-2642.1 k
-2569.7 m
-2555.2 n
-2563.9 o
-2526.5 q
-2561.3 r

0.0 i
-3188.0 j
-3148.9 k
-3080.4 m
-3075.2 n
-3086.3 o
-3052.2 q
-3065.3 r
 
0.0 i
-3188.0 j
-3148.9 k
-3080.4 m
-3075.2 n
-3086.3 o
-3052.2 q
-3065.3 r
MP2FC// B3LYP/6-31G*  
0.0 i
-430.9 j
-373.8 k
-369.9 m
-370.0 n
-800.4 o
-350.9 q
-346.1 r
     
MP2FC// MP2FC/6-31G*
NC

0.0 i
-384.0 k
-360.9 q
 
0.0 i
-442.0 j
-388.2 k
-383.0 m
-384.6 n
-380.5 o
-364.9 q
-357.9 r
 
MP4// MP2/6-31G*
NC
       
Coupled Cluster CCSD// MP2FC/6-31G*
NC
       
CCSD(T)// MP2FC/6-31G*
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 Calculated; Vibrations; Scale Factors; Scale factors to list vibrational scaling factors.
See section Calculated; Vibrations; Scale Factors; Calculate a scale factor to calculate a vibrational scaling factor for a given set of molecules.