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

Geometry Comparison

HClO4 (perchloric acid)


distance is atom 1 (Cl) to atom 4 (O)

Experimental bond length is 1.404  Å

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Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM6 1.426
composite G2 1.416
G3 1.416
G3B3 1.442
G4 1.424
CBS-Q 1.415

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) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ
hartree fock HF 2.254 2.199 1.422 2.104 1.416 1.416 1.416 1.408 1.408 1.385 1.422 1.427 1.393 1.434 1.393 1.378 1.421 1.379
density functional LSDA 1.766 1.460 1.460 1.671 1.460 1.460 1.462 1.454 1.454 1.427 1.466 1.473 1.436 1.478 1.437 1.417 1.466 1.418
SVWN   1.631     1.460 1.460 1.462 1.454 1.454 1.427   1.473 1.436 1.478 1.437 1.417 1.466 1.418
BLYP 1.830 1.686 1.502 1.728 1.497 1.497 1.502 1.495 1.495 1.461 1.508 1.513 1.471     1.449 1.505 1.450
B1B95 1.792 1.449 1.449 1.684 1.446 1.446 1.447 1.440 1.439 1.416 1.452 1.458 1.424 1.464 1.425 1.407 1.451 1.408
B3LYP 1.811 1.655 1.468 1.702 1.465 1.465 1.467 1.460 1.460 1.431 1.473 1.479 1.440 1.484 1.442 1.421 1.472 1.422
B3LYPultrafine         1.465                   1.430      
B3PW91 1.793 1.642 1.459 1.687 1.456 1.456 1.457 1.450 1.449 1.424 1.462 1.468 1.433     1.415 1.461 1.415
mPW1PW91 1.793 1.636 1.452 1.684 1.450 1.450 1.451 1.443 1.443 1.419 1.456 1.461 1.427 1.467 1.428 1.410 1.455 1.410
M06-2X 1.818 1.628 1.449 1.678 1.444 1.444 1.445 1.438 1.438 1.415 1.450 1.455 1.424 1.461 1.425 1.408 1.449 1.409
PBEPBE 1.803 1.664 1.484 1.704 1.480 1.480 1.482 1.475 1.475 1.448 1.488 1.493 1.457 1.499 1.458 1.437 1.486 1.438
PBE1PBE 1.787 1.451 1.451 1.680 1.449 1.449 1.450 1.442 1.442 1.419 1.455 1.460 1.427 1.466 1.428 1.410 1.454 1.410
HSEh1PBE 1.790 1.636 1.452 1.683 1.450 1.450 1.451 1.444 1.443 1.419 1.456 1.462 1.427 1.467 1.428 1.410 1.455 1.411
TPSSh         1.443   1.444           1.430          
Moller Plesset perturbation MP2   1.600 1.453 1.647 1.451 1.451 1.454 1.438 1.438 1.419 1.453 1.458 1.427 1.469 1.430 1.412 1.453 1.413
MP2=FULL   1.600 1.453 1.647 1.450 1.450 1.452 1.438 1.437 1.417 1.452 1.456 1.424 1.467 1.426 1.409 1.453 1.410
MP3         1.443   1.432                      
MP3=FULL         1.432   1.432                      
MP4         1.468       1.456       1.440     1.425   1.425
B2PLYP         1.442                          
Configuration interaction CID   1.657 1.436 1.746 1.430     1.417                    
CISD   1.661 1.439 1.743 1.432     1.419                    
Quadratic configuration interaction QCISD   1.692 1.464   1.458 1.458 1.461 1.445 1.445 1.418 1.461 1.467 1.425 1.480 1.428 1.409 1.461 1.410
QCISD(T)         1.467   1.471   1.455   1.472 1.477 1.435     1.418 1.471 1.418
Coupled Cluster CCD   1.648 1.447 1.717 1.444 1.444 1.446 1.431 1.431 1.409 1.446 1.451 1.415       1.446  
CCSD         1.454             1.462 1.422     1.406 1.456 1.407
CCSD(T)         1.465   1.468   1.452   1.469 1.474 1.433     1.416 1.468 1.417
CCSD(T)=FULL         1.463           1.468 1.473 1.429     1.413   1.414

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 2.112 1.441 2.085 1.438 2.259 2.238
density functional B3LYP 1.733 1.492 1.726 1.489 1.719 1.712
Moller Plesset perturbation MP2 1.683 1.475 1.663 1.473 1.649 1.635
Values that are outliers may reflect incorrect atom numbering for different levels of theory.
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