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

Isomers of C8H8

17 10 10 15 39
index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C6H5CHCH2 100425 Styrene   sketch of Styrene
b C8H8 277101 cubane   sketch of cubane
c C8H8 629209 cyclooctatetraene   sketch of cyclooctatetraene
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets

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 daug-cc-pVTZ
hartree fock HF 0.0 a
158.6 b
197.2 c
0.0 a
466.4 b
170.2 c
0.0 a
466.4 b
170.2 c
0.0 a
594.1 b
174.4 c
0.0 a
507.4 b
161.6 c
0.0 a
508.5 b
161.7 c
0.0 a
527.0 b
159.5 c
0.0 a
519.3 b
156.4 c
0.0 a
521.6 b
157.5 c
0.0 a
507.7 b
155.5 c
0.0 a
532.0 b
156.2 c
0.0 a
534.6 b
159.4 c
0.0 a
517.3 b
158.9 c
0.0 a
536.6 b
157.7 c
0.0 a
514.9 b
156.3 c
0.0 a
538.2 b
157.1 c
0.0 a
536.7 b
157.7 c

NC
NC
density functional BLYP 0.0 a
265.6 b
190.1 c
0.0 a
444.1 b
162.4 c
0.0 a
444.1 b
162.4 c
0.0 a
574.1 b
167.3 c
0.0 a
515.8 b
163.9 c
0.0 a
515.6 b
163.5 c
0.0 a
530.4 b
159.3 c
0.0 a
533.7 b
155.8 c
0.0 a
534.8 b
0.0 a
516.1 b
    0.0 a
510.8 b
160.5 c
0.0 a
552.4 b
157.7 c
0.0 a
522.5 b
156.3 c
  0.0 a
552.6 b
157.7 c
 
B1B95 0.0 a
161.5 b
203.3 c
0.0 a
346.1 b
165.1 c
0.0 a
346.1 b
165.1 c
0.0 a
474.7 b
173.7 c
0.0 a
401.9 b
170.0 c
0.0 a
441.3 b
169.6 c
0.0 a
422.1 b
165.9 c
0.0 a
421.3 b
162.9 c
0.0 a
422.2 b
163.7 c
0.0 a
403.9 b
169.4 c
    0.0 a
404.0 b
166.2 c
0.0 a
424.2 b
167.8 c
0.0 a
404.9 b
164.7 c
  0.0 a
424.2 b
167.8 c
 
B3LYP 0.0 a
227.8 b
196.7 c
0.0 a
429.8 b
166.6 c
0.0 a
429.8 b
166.6 c
0.0 a
558.3 b
172.3 c
0.0 a
494.4 b
167.9 c
0.0 a
494.5 b
167.6 c
0.0 a
509.8 b
163.7 c
0.0 a
512.6 b
160.2 c
0.0 a
514.2 b
161.0 c
0.0 a
497.0 b
159.7 c
0.0 a
528.3 b
0.0 a
530.9 b
161.9 c
0.0 a
492.6 b
164.6 c
0.0 a
531.6 b
162.5 c
0.0 a
504.7 b
161.3 c
0.0 a
532.7 b
161.8 c
0.0 a
531.6 b
162.5 c
 
B3LYPultrafine         0.0 a
494.4 b
                    0.0 a
532.5 b
161.6 c
   
B3PW91 0.0 a
186.6 b
202.4 c
0.0 a
364.5 b
167.5 c
0.0 a
364.5 b
167.5 c
0.0 a
494.7 b
173.9 c
0.0 a
431.5 b
169.6 c
0.0 a
431.6 b
169.3 c
0.0 a
443.2 b
165.6 c
0.0 a
444.7 b
162.2 c
0.0 a
446.1 b
163.3 c
0.0 a
431.6 b
    0.0 a
427.5 b
165.6 c
0.0 a
460.2 b
165.5 c
0.0 a
436.8 b
163.5 c
  0.0 a
460.2 b
165.5 c
 
mPW1PW91 0.0 a
170.7 b
204.0 c
0.0 a
344.9 b
167.5 c
0.0 a
344.9 b
167.5 c
0.0 a
483.1 b
180.9 c
0.0 a
412.3 b
169.8 c
0.0 a
412.5 b
169.7 c
0.0 a
425.0 b
165.8 c
0.0 a
431.7 b
169.0 c
0.0 a
433.2 b
163.8 c
0.0 a
418.9 b
    0.0 a
409.1 b
166.0 c
0.0 a
447.5 b
172.4 c
0.0 a
424.3 b
  0.0 a
453.7 b
172.4 c
 
M06-2X     0.0 a
380.6 b
155.4 c
  0.0 a
445.7 b
162.8 c
                         
PBEPBE 0.0 a
204.3 b
197.7 c
0.0 a
351.1 b
162.9 c
0.0 a
351.1 b
162.8 c
0.0 a
487.0 b
169.0 c
0.0 a
427.4 b
165.6 c
0.0 a
427.2 b
165.2 c
0.0 a
439.3 b
160.7 c
0.0 a
438.5 b
157.7 c
0.0 a
439.6 b
158.5 c
0.0 a
424.0 b
158.2 c
    0.0 a
419.9 b
161.6 c
0.0 a
453.4 b
160.8 c
0.0 a
430.8 b
  0.0 a
453.7 b
160.8 c
 
PBEPBEultrafine         0.0 a
427.4 b
                         
PBE1PBE         0.0 a
407.3 b
169.7 c
                         
HSEh1PBE   0.0 a
354.0 b
167.4 c
    0.0 a
420.2 b
169.3 c
  0.0 a
432.9 b
165.1 c
            0.0 a
448.7 b
165.2 c
       
TPSSh         0.0 a
430.4 b
170.2 c
  0.0 a
441.9 b
166.0 c
    0.0 a
428.7 b
169.3 c
      0.0 a
456.4 b
166.9 c
       
wB97X-D    
NC
NC
 
NC
NC
 
NC
NC
 
NC
NC
   
NC
NC

NC
NC

NC
NC
  0.0 a
439.5 b
158.1 c
   
B97D3  
NC
NC
    0.0 a
506.5 b
161.5 c
  0.0 a
518.6 b
157.1 c
 
NC
NC
 
NC
NC
0.0 a
536.9 b
156.9 c
 
NC
NC
  0.0 a
537.6 b
155.9 c
   
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 daug-cc-pVTZ
Moller Plesset perturbation MP2 0.0 a
278.5 b
187.4 c
0.0 a
473.1 b
159.1 c
0.0 a
473.1 b
159.1 c
0.0 a
590.8 b
162.2 c
0.0 a
472.3 b
174.5 c
0.0 a
470.7 b
174.3 c
0.0 a
492.9 b
168.5 c

NC
NC
0.0 a
458.4 b
168.9 c
0.0 a
432.7 b
  0.0 a
489.4 b
0.0 a
458.7 b
172.7 c

NC
NC
       
MP2=FULL   0.0 a
472.1 b
159.3 c

NC
NC
0.0 a
589.1 b
162.5 c
0.0 a
464.9 b
174.6 c
0.0 a
463.5 b
174.9 c
0.0 a
485.9 b
169.2 c
0.0 a
457.7 b
168.7 c
0.0 a
453.6 b
169.4 c
      0.0 a
458.0 b
173.2 c
         
MP3         0.0 a
459.9 b
                         
MP3=FULL         0.0 a
452.8 b
153.2 c
  0.0 a
473.8 b
149.8 c
                     
B2PLYP         0.0 a
488.8 b
168.3 c
               
NC
NC
       
Configuration interaction CID        
NC
NC
                         
CISD        
NC
NC
                         
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 daug-cc-pVTZ
Quadratic configuration interaction QCISD   0.0 a
444.7 b
                               
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 daug-cc-pVTZ

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF 0.0 a
534.6 b
180.6 c
0.0 a
428.5 b
167.2 c
0.0 a
553.1 b
173.2 c
0.0 a
485.1 b
158.6 c
0.0 a
582.8 b
176.6 c
0.0 a
579.8 b
176.7 c
   
NC
NC
density functional B1B95 0.0 a
382.6 b
181.6 c
0.0 a
305.5 b
176.7 c
             
B3LYP 0.0 a
478.5 b
178.8 c
0.0 a
417.5 b
173.7 c
0.0 a
513.3 b
171.0 c
0.0 a
470.5 b
164.9 c
0.0 a
522.6 b
175.5 c
0.0 a
522.6 b
175.5 c
    0.0 a
531.5 b
162.4 c
PBEPBE                 0.0 a
453.7 b
160.7 c
Moller Plesset perturbation MP2 0.0 a
526.0 b
169.4 c
0.0 a
384.5 b
177.6 c
0.0 a
534.1 b
149.6 c
0.0 a
431.2 b
163.3 c
0.0 a
561.4 b
160.4 c
0.0 a
559.5 b
160.3 c
   
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 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.