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

Isomers of C3H3

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C3H3+ 2932787 Propargyl cation   sketch of Propargyl cation
b C3H3+ 9000220 cyclopropenyl cation 0.0 sketch of cyclopropenyl cation
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM3 23.0 a
0.0 b
PM6 1066.4 a
composite G1 104.6 a
0.0 b
G2MP2 107.0 a
0.0 b
G2 107.3 a
0.0 b
G3 104.5 a
0.0 b
G3B3 105.8 a
0.0 b
G3MP2 103.1 a
0.0 b
G4 108.4 a
0.0 b
CBS-Q 105.6 a
0.0 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) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ daug-cc-pVTZ
hartree fock HF 141.9 a
0.0 b
48.6 a
0.0 b
48.6 a
0.0 b
64.5 a
0.0 b
141.9 a
0.0 b
143.1 a
0.0 b
140.8 a
0.0 b
135.5 a
0.0 b
137.9 a
0.0 b
146.1 a
0.0 b
  136.1 a
0.0 b
141.5 a
0.0 b
142.6 a
0.0 b
143.5 a
0.0 b
142.6 a
0.0 b
142.6 a
0.0 b
143.5 a
0.0 b
142.7 a
0.0 b
density functional LSDA 122.1 a
0.0 b
67.2 a
0.0 b
67.2 a
0.0 b
81.9 a
0.0 b
130.5 a
0.0 b
131.3 a
0.0 b
129.6 a
0.0 b
122.9 a
0.0 b
125.3 a
0.0 b
132.1 a
0.0 b
    130.3 a
0.0 b
128.0 a
0.0 b
128.6 a
0.0 b
129.2 a
0.0 b
127.8 a
0.0 b
128.5 a
0.0 b
 
BLYP NC NC NC NC 85.9 a
0.0 b
NC NC NC NC NC     NC NC          
B1B95 129.7 a
0.0 b
70.8 a
0.0 b
70.9 a
0.0 b
86.5 a
0.0 b
141.3 a
0.0 b
142.2 a
0.0 b
140.6 a
0.0 b
134.9 a
0.0 b
137.2 a
0.0 b
142.4 a
0.0 b
    141.3 a
0.0 b
139.3 a
0.0 b
140.5 a
0.0 b
140.8 a
0.0 b
139.3 a
0.0 b
140.4 a
0.0 b
 
B3LYP 103.7 a
0.0 b
42.8 a
0.0 b
42.8 a
0.0 b
56.5 a
0.0 b
107.9 a
0.0 b
108.9 a
0.0 b
106.5 a
0.0 b
100.0 a
0.0 b
102.4 a
0.0 b
108.5 a
0.0 b
  101.8 a
0.0 b
107.4 a
0.0 b
104.1 a
0.0 b
105.0 a
0.0 b
106.1 a
0.0 b
104.1 a
0.0 b
105.0 a
0.0 b
 
B3LYPultrafine         107.9 a
0.0 b
                      104.1 a
0.0 b
   
B3PW91 NC NC NC NC NC NC NC NC NC NC     NC NC          
mPW1PW91 124.2 a
0.0 b
63.5 a
0.0 b
63.5 a
0.0 b
77.2 a
0.0 b
132.8 a
0.0 b
133.8 a
0.0 b
132.2 a
0.0 b
126.5 a
0.0 b
128.8 a
0.0 b
134.6 a
0.0 b
    133.3 a
0.0 b
130.9 a
0.0 b
         
M06-2X     71.2 a
0.0 b
  NC                            
PBEPBE 106.1 a
0.0 b
52.7 a
0.0 b
52.7 a
0.0 b
65.1 a
0.0 b
113.3 a
0.0 b
114.2 a
0.0 b
112.3 a
0.0 b
107.0 a
0.0 b
109.2 a
0.0 b
114.4 a
0.0 b
    113.7 a
0.0 b
110.2 a
0.0 b
111.3 a
0.0 b
    111.3 a
0.0 b
 
PBE1PBE         136.6 a
0.0 b
                           
TPSSh         123.5 a
0.0 b
  122.9 a
0.0 b
    124.5 a
0.0 b
      120.9 a
0.0 b
         
wB97X-D     61.7 a
0.0 b
  130.4 a
0.0 b
  129.8 a
0.0 b
  125.8 a
0.0 b
    125.4 a
0.0 b
129.8 a
0.0 b
129.2 a
0.0 b
    129.1 a
0.0 b
   
B97D3   40.2 a
0.0 b
    105.3 a
0.0 b
  104.5 a
0.0 b
  100.8 a
0.0 b
  103.3 a
0.0 b
98.9 a
0.0 b
  101.6 a
0.0 b
    101.6 a
0.0 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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ daug-cc-pVTZ
Moller Plesset perturbation MP2 109.9 a
0.0 b
36.0 a
0.0 b
36.0 a
0.0 b
53.9 a
0.0 b
133.6 a
0.0 b
134.5 a
0.0 b
132.7 a
0.0 b
126.3 a
0.0 b
128.8 a
0.0 b
134.4 a
0.0 b
  128.4 a
0.0 b
128.3 a
0.0 b
130.9 a
0.0 b

0.0 b
126.5 a
0.0 b
130.9 a
0.0 b

0.0 b
 
MP2=FULL 110.1 a
0.0 b
36.1 a
0.0 b
36.1 a
0.0 b
54.0 a
0.0 b
133.9 a
0.0 b
134.8 a
0.0 b
132.9 a
0.0 b
127.2 a
0.0 b
129.9 a
0.0 b
136.5 a
0.0 b
    128.7 a
0.0 b
133.8 a
0.0 b

0.0 b
  132.5 a
0.0 b

0.0 b
 
ROMP2
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
   
0.0 b

0.0 b

0.0 b

0.0 b

0.0 b

0.0 b
 
MP3         137.5 a
0.0 b
                           
MP3=FULL         137.7 a
0.0 b
  136.5 a
0.0 b
                       
MP4   23.3 a
0.0 b
    114.9 a
0.0 b
      111.2 a
0.0 b
                   
B2PLYP         NC                 108.7 a
0.0 b
         
Configuration interaction CID   NC NC NC NC     NC                      
CISD   NC NC NC 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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ daug-cc-pVTZ
Quadratic configuration interaction QCISD   23.9 a
0.0 b
23.9 a
0.0 b
39.9 a
0.0 b
119.8 a
0.0 b
120.2 a
0.0 b
118.7 a
0.0 b
114.3 a
0.0 b
116.3 a
0.0 b
122.6 a
0.0 b
    115.2 a
0.0 b
120.4 a
0.0 b
         
QCISD(T)         NC               NC NC   NC NC    
Coupled Cluster CCD   38.1 a
0.0 b
38.1 a
0.0 b
55.7 a
0.0 b
134.1 a
0.0 b
134.8 a
0.0 b
133.1 a
0.0 b
127.7 a
0.0 b
129.9 a
0.0 b
135.1 a
0.0 b
    128.9 a
0.0 b
132.5 a
0.0 b
  127.8 a
0.0 b
132.8 a
0.0 b
   
CCSD         NC                            
CCSD(T)         NC               NC NC   NC NC    
CCSD(T)=FULL         114.3 a
0.0 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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ 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 78.9 a
0.0 b
159.3 a
0.0 b
64.4 a
0.0 b
141.3 a
0.0 b
58.0 a
0.0 b
57.6 a
0.0 b
    143.0 a
0.0 b
density functional B3LYP 65.7 a
0.0 b
119.2 a
0.0 b
53.6 a
0.0 b
104.8 a
0.0 b
52.3 a
0.0 b
52.5 a
0.0 b
    105.0 a
0.0 b
PBEPBE                 111.0 a
0.0 b
Moller Plesset perturbation MP2 69.4 a
0.0 b
145.7 a
0.0 b
57.9 a
0.0 b
134.3 a
0.0 b
52.4 a
0.0 b
52.1 a
0.0 b
    131.6 a
0.0 b
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.