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

Isomers of CH3O2

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH3OO 2143580 methylperoxy radical   sketch of methylperoxy radical
b CH2OOH 9000344 CH2OOH radical   sketch of CH2OOH radical
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM3 122.0 a
-143.0 b
composite G1 NC
NC
G2MP2 NC
NC
G2 NC
NC
G3 NC
NC
G3B3 NC
NC
G3MP2 NC
G4 NC
NC
CBS-Q NC
NC

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 cc-pV(T+d)Z daug-cc-pVTZ
hartree fock HF NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC NC
NC
ROHF NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC     NC
NC
NC
NC
  NC
NC
NC
NC
NC  
density functional LSDA NC
NC
NC NC NC NC NC NC NC NC NC     NC NC   NC   NC  
BLYP NC
NC
NC NC NC NC NC NC NC NC NC     NC NC       NC  
B1B95
NC
     
NC

NC
NC
NC

NC

NC

NC
   
NC

NC
 
NC

NC
   
B3LYP NC
NC
NC NC NC NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
  NC NC
NC
NC
NC
  NC NC NC  
B3LYPultrafine         NC
NC
  NC             NC     NC    
B3PW91 NC
NC
NC NC NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
    NC
NC
NC
NC
      NC  
mPW1PW91 NC
NC
NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
    NC
NC
NC
NC
 
NC

NC
NC  
M06-2X     NC   NC                            
PBEPBE NC
NC
NC NC NC NC NC NC NC NC NC     NC NC       NC  
PBEPBEultrafine         NC                            
PBE1PBE         NC                            
HSEh1PBE   NC     NC   NC             NC          
TPSSh         NC
NC
  NC
NC
    NC
NC
      NC
NC
         
wB97X-D     NC
NC
  NC
NC
  NC
NC
  NC
NC
    NC
NC
NC
NC
NC
NC
    NC
NC
   
B97D3   NC     NC
NC
  NC   NC
NC
  NC
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 cc-pV(T+d)Z daug-cc-pVTZ
Moller Plesset perturbation MP2 NC
NC
NC NC NC NC
NC
NC
NC

NC
NC
NC
NC
NC
NC
NC
  NC
NC
NC
NC
NC
NC
  NC
NC

NC
NC  
MP2=FULL NC
NC
NC NC NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
    NC
NC
NC
NC
 
NC

NC
NC  
ROMP2
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
   
NC

NC
 
NC
     
MP3        
NC
  NC                        
MP3=FULL         NC
NC
  NC
NC
                       
MP4   NC     NC
NC
      NC
NC
       
NC
         
B2PLYP         NC   NC   NC         NC
NC
         
B2PLYP=FULL   NC     NC   NC                        
Configuration interaction CID   NC NC NC NC
NC
    NC
NC
                     
CISD   NC NC 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 cc-pV(T+d)Z daug-cc-pVTZ
Quadratic configuration interaction QCISD   NC
NC
NC
NC
NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
    NC
NC

NC
 
NC

NC
   
QCISD(T)         NC
NC
             
NC
           
Coupled Cluster CCD   NC NC NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
   
NC

NC
 
NC

NC
   
CCSD         NC
NC
             
NC

NC
         
CCSD(T)         NC
NC
             
NC
   
NC
     
CCSD(T)=FULL        
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 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 NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
    NC
NC
density functional B1B95 NC NC              
B3LYP NC NC
NC
NC NC
NC
NC NC     NC
NC
PBEPBE                 NC
Moller Plesset perturbation MP2 NC NC
NC
NC NC
NC
NC NC     NC
NC

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* NC   NC   NC
MP2FC// B3LYP/6-31G* NC NC NC   NC
MP2FC// MP2FC/6-31G*     NC NC NC
MP4// HF/6-31G*         NC
MP4// B3LYP/6-31G*         NC
MP4// MP2/6-31G*         NC
Coupled Cluster CCSD// B3LYP/6-31G* NC        
CCSD(T)//B3LYP/6-31G(2df,p)     NC   NC
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.