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IV.D.1. (XII.C.1.)

Geometry Comparison

H2Se (Hydrogen selenide)


distance is atom 1 (Se) to atom 2 (H)

Experimental bond length is 1.460  Å

original data displayed. press to display differences
differences displayed. press to display original data

Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM3 1.469
PM6 1.462
composite G2 1.467

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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
hartree fock HF 1.440 1.471 1.464 1.454 1.467 1.444 1.443 1.462 1.454   1.453 1.453 1.458 1.454 1.453 1.458   1.453
density functional LSDA 1.464 1.503 1.486 1.485 1.490 1.465 1.466 1.484 1.475 1.468     1.483 1.474   1.483    
SVWN   1.503     1.490   1.466                      
BLYP 1.474 1.511 1.497 1.494 1.500 1.474 1.475 1.494 1.485 1.478     1.494 1.484        
B1B95 1.460 1.489 1.476 1.472   1.455 1.455 1.474 1.466 1.459     1.472 1.463   1.470    
B3LYP 1.463 1.496 1.483 1.479 1.486 1.461 1.462 1.480 1.472 1.465   1.471 1.479 1.471 1.470 1.479 1.471 1.470
B3PW91 1.463 1.495 1.481 1.476 1.483 1.458 1.458 1.478 1.469 1.462     1.475 1.468        
mPW1PW91 1.460 1.491 1.478 1.472 1.479 1.455 1.455 1.475 1.466 1.460     1.472 1.465        
M06-2X         1.479                          
PBEPBE 1.472 1.510 1.493 1.490 1.495 1.495 1.470 1.490 1.481 1.473     1.488 1.481   1.487 1.481  
HSEh1PBE         1.482                          
Moller Plesset perturbation MP2FC 1.457 1.488 1.475 1.472 1.482 1.448 1.448 1.476 1.458 1.455   1.451 1.462 1.450   1.465    
MP2FU 1.457 1.488 1.475 1.471 1.481 1.446 1.446 1.474 1.454 1.446     1.461 1.444   1.464    
MP4   1.500     1.491                 1.457        
B2PLYP         1.482   1.455                      
Configuration interaction CID         1.486                          
CISD         1.487                          
Quadratic configuration interaction QCISD 1.473 1.503 1.485 1.485 1.491 1.454   1.487 1.464 1.460     1.469 1.456        
QCISD(T)         1.493                 1.458        
Coupled Cluster CCD 1.472 1.501 1.484 1.483 1.490 1.452   1.485 1.463 1.459     1.467          
CCSD         1.491                          
CCSD(T)   1.504 1.487 1.486 1.493   1.455 1.489         1.470 1.458   1.473    

Calculated bond length in Å
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 1.477   1.475   1.473 1.466
density functional B1B95 1.504          
B3LYP 1.504   1.502   1.498 1.493
Moller Plesset perturbation MP2FC 1.500   1.498   1.491 1.486
Values that are outliers may reflect different atom numbering for different levels of theory.
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