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

Isomers of C2H6N2

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a H2NCHCHNH2 4013438 diaminoethylene   sketch of diaminoethylene
b CH3NNCH3 4143413 (E)-1,2-Dimethyldiazene   sketch of (E)-1,2-Dimethyldiazene
c CH3NNCH3 4143424 (Z)-1,2-Dimethyldiazene   sketch of (Z)-1,2-Dimethyldiazene
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1 267.5 a
348.2 c
PM3 277.3 a
327.6 b
336.5 c
PM6 263.6 a
318.7 c
composite G1 NC
NC
NC
G2MP2 NC
NC
NC
G2 NC
NC
NC
G3 NC
NC
NC
G3B3 NC
NC
NC
G4 NC
NC
NC
CBS-Q NC
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 aug-cc-pVDZ aug-cc-pVTZ 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
density functional LSDA
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
 
BLYP
NC
NC

NC
NC

NC
NC

NC

NC
NC

NC
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
NC

NC
NC

NC
NC

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

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
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

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
 
PBEPBE
NC

NC

NC

NC

NC

NC

NC

NC

NC

NC
 
NC

NC

NC

NC

NC
 
PBEPBEultrafine        
NC
             
NC

NC

NC

NC
 
PBE1PBE
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
 
HSEh1PBE
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
 
TPSSh  
NC

NC

NC

NC

NC

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
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 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
 
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
 
MP3        
NC
 
NC
                   
MP3=FULL        
NC
 
NC
                   
MP4  
NC
NC
   
NC
     
NC
   
NC

NC
NC

NC

NC
NC

NC
NC
 
MP4=FULL  
NC
NC
   
NC
NC
     
NC
     
NC
NC

NC
NC

NC
NC

NC
NC
 
B2PLYP
NC
NC

NC
NC

NC
NC

NC

NC
NC

NC
NC

NC

NC

NC

NC
NC
 
NC

NC
NC

NC
NC

NC
NC
   
B2PLYP=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
 
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 aug-cc-pVDZ aug-cc-pVTZ daug-cc-pVTZ
Quadratic configuration interaction QCISD  
NC

NC

NC

NC

NC

NC

NC

NC

NC
 
NC

NC

NC

NC

NC
 
QCISD(T)        
NC
           
NC

NC
NC

NC
NC

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
NC
 
CCSD        
NC
           
NC

NC
NC

NC

NC

NC
NC
 
CCSD=FULL        
NC
           
NC

NC

NC

NC
   
CCSD(T)        
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 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
-88187.8 b
-88131.4 c

-88446.4 b
-88394.4 c

-88211.9 b

-88477.3 b

NC

NC
   
NC
NC
density functional B3LYP
-90633.1 b
-90596.0 c

-90802.0 b
-90765.0 c

-90668.4 b

-90845.1 b

NC

NC
   
NC
NC
PBEPBE                
NC
NC
Moller Plesset perturbation MP2
-89163.5 b
-89125.6 c

-89913.3 b
-89873.8 c

-89296.0 b

-90046.0 b

NC

NC
   
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.