return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Comparisons > Energy > Similar molecules > Isomers OR FAQ Help > List > Similar molecules > Isomers

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

Isomers of C4H4O

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH3COCCH 1423605 3-butyn-2-one   sketch of 3-butyn-2-one
b C4H4O 110009 Furan 0.0 sketch of Furan
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1
0.0 b
PM3
0.0 b
MNDOd
0.0 b
composite G1 94.5 a
0.0 b
G2MP2 97.6 a
0.0 b
G2 96.2 a
0.0 b
G3 95.6 a
0.0 b
G3B3 94.7 a
0.0 b
G3MP2
0.0 b
G4 NC
0.0 b
CBS-Q 90.3 a
0.0 b
molecular mechanics MM3
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 aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z daug-cc-pVTZ
hartree fock HF   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a
0.0 b
  a
density functional LSDA NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC    
BLYP   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
B1B95   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a
0.0 b
 
B3LYP   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a
0.0 b
 
B3LYPultrafine     a       a   a   a   a       a   a   a   a   a   a    
B3PW91   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a
0.0 b
 
mPW1PW91   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a
0.0 b
 
M06-2X   a   a   a   a   a   a   a   a   a   a     a   a   a   a   a    
PBEPBE   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a
0.0 b
 
PBEPBEultrafine     a       a   a   a   a       a   a   a   a   a   a    
PBE1PBE   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
HSEh1PBE   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
TPSSh   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
wB97X-D   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
B97D3   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
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   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a
0.0 b
 
MP2=FULL   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
MP3         117.0 a
0.0 b
    a       NC NC NC NC        
MP3=FULL   NC NC NC 117.6 a
0.0 b
NC 118.6 a
0.0 b
NC NC NC NC NC NC NC NC      
MP4   NC     NC       NC   NC NC NC NC NC      
MP4=FULL   NC     NC       NC       NC NC NC      
B2PLYP   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
B2PLYP=FULL   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a   a    
Configuration interaction CID   NC NC NC 111.9 a
0.0 b
    NC     NC              
CISD   NC NC NC 110.4 a
0.0 b
    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   70.1 a
0.0 b
NC NC   a 103.1 a
0.0 b
101.4 a
0.0 b
NC 93.3 a
0.0 b
NC   NC NC   NC      
QCISD(T)         NC     NC     NC   NC NC NC      
QCISD(T)=FULL           a     a         a     a     a      
Coupled Cluster CCD   NC NC NC 107.0 a
0.0 b
NC NC NC NC NC   NC NC NC NC      
CCSD         NC         NC   NC NC   NC      
CCSD=FULL         NC         NC NC NC NC NC NC      
CCSD(T)         NC NC NC NC NC NC   NC NC NC NC      
CCSD(T)=FULL         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 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   a   a   a   a   a   a       a
density functional B1B95
0.0 b

0.0 b
             
B3LYP   a   a   a   a   a   a       a
PBEPBE                   a
wB97X-D   a   a   a   a   a   a      
Moller Plesset perturbation MP2   a   a   a   a   a   a       a

Single point energy calculations (select basis sets)
cc-pVDZ cc-pVTZ aug-cc-pVDZ cc-pV(T+d)Z
Moller Plesset perturbation MP2FC// HF/6-31G*
0.0 b

0.0 b
 
0.0 b
MP2FC// B3LYP/6-31G*
0.0 b
     
MP2FC// MP2FC/6-31G*
0.0 b

0.0 b

0.0 b

0.0 b
MP4// HF/6-31G*
0.0 b
     
Coupled Cluster CCSD// HF/6-31G*
0.0 b

0.0 b
 
0.0 b
CCSD(T)// HF/6-31G*
0.0 b

0.0 b
 
0.0 b
CCSD(T)//B3LYP/6-31G(2df,p)  
0.0 b
 
0.0 b
CCSD// MP2FC/6-31G*
0.0 b

0.0 b
 
0.0 b
CCSD(T)// MP2FC/6-31G*
0.0 b

0.0 b
 
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.