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: Home > Geometry > Comparisons > Bonds, angles OR Comparisons > Geometry > Bonds, angles

Geometry Comparison

C4H4N2 (1,3-Diazine)


distance is atom 2 (C) to atom 6 (N)

Experimental bond length is 1.328  Å

Display Options
Switch to bar chart display
Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM3 1.357
PM6 1.376
composite G2 1.319
G3 1.319
G3B3 1.338
G4 1.333

Calculated bond length in Å
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 1.354 1.329 1.329 1.330 1.318 1.319 1.319 1.317 1.318 1.316 1.315 1.316 1.320 1.315 1.321 1.315 1.315
density functional BLYP 1.413 1.365   1.365 1.348 1.351 1.352   1.348 1.348     1.353 1.345 1.352    
B1B95 1.383 1.345 1.345 1.345 1.330 1.332 1.332 1.329 1.329 1.329     1.333 1.325 1.331    
B3LYP 1.392 1.350 1.350 1.351 1.338 1.338 1.339 1.335   1.334 1.332 1.334 1.339 1.332   1.332  
B3LYPultrafine         1.338   1.339             1.333   1.331  
B3PW91   1.348 1.348 1.348 1.335 1.335   1.332   1.332     1.336 1.330 1.336    
mPW1PW91   1.345   1.346 1.332 1.332 1.333 1.329 1.330 1.329     1.334   1.333    
M06-2X     1.347   1.333                        
PBEPBE   1.361     1.346 1.346 1.347 1.343 1.343 1.343 1.340   1.347 1.341      
PBEPBEultrafine         1.345                        
PBE1PBE         1.332                        
HSEh1PBE   1.343     1.333   1.334             1.328      
TPSSh         1.339   1.339     1.337       1.333      
wB97X-D     1.345   1.333   1.334   1.331     1.329 1.334 1.328   1.328  
B97D3   1.358     1.345   1.345   1.342   1.339 1.340   1.339   1.339  
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   1.366 1.366 1.369 1.342 1.342 1.343 1.341 1.341 1.338   1.338 1.347 1.337      
MP2=FULL         1.341     1.340                  
MP3         1.337   1.337                    
MP3=FULL         1.336   1.337                    
B2PLYP         1.339                 1.334      
B2PLYP=FULLultrafine         1.339                        
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                 1.339                
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

Calculated bond length in Å
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 1.344 1.330 1.342 1.326 1.336 1.336     1.313
density functional B1B95 1.361 1.345              
B3LYP 1.369 1.351 1.365 1.346 1.357 1.358     1.332
PBEPBE                 1.341
Moller Plesset perturbation MP2 1.391 1.357 1.383 1.352 1.379 1.379     1.337
Values that are outliers may reflect incorrect atom numbering for different levels of theory.
Please use the error report form to report problems.