Geometry Comparison
CH3CH(NH2)COOH (Alanine)
distance is atom 2 (C) to atom 3 (C)
Experimental bond length is 1.509 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 |
AM1 |
1.527 |
| PM3 |
1.522 |
| PM6 |
1.538 |
| composite |
G2 |
1.526 |
| G3 |
1.526 |
| G3B3 |
1.530 |
| CBS-Q |
1.528 |
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 |
| hartree fock |
HF |
|
1.531 |
1.531 |
1.530 |
1.526 |
1.526 |
1.527 |
1.525 |
1.525 |
1.526 |
1.524 |
1.524 |
1.524 |
1.523 |
1.526 |
| density functional |
LSDA |
1.530 |
1.508 |
1.508 |
1.510 |
1.507 |
1.506 |
1.509 |
1.503 |
1.504 |
1.506 |
|
|
1.506 |
1.502 |
1.510 |
| SVWN |
|
1.515 |
|
|
1.507 |
|
1.513 |
|
|
|
|
|
|
|
|
| BLYP |
|
1.543 |
1.543 |
1.545 |
1.541 |
1.540 |
1.543 |
1.539 |
1.540 |
1.540 |
|
|
1.539 |
1.538 |
1.542 |
| B1B95 |
|
1.524 |
1.524 |
1.525 |
1.520 |
1.520 |
1.522 |
1.518 |
1.519 |
1.520 |
|
|
1.518 |
1.517 |
1.520 |
| B3LYP |
|
1.533 |
1.533 |
1.534 |
1.530 |
1.529 |
1.531 |
1.528 |
1.529 |
1.529 |
|
1.529 |
1.528 |
1.526 |
1.530 |
| B3LYPultrafine |
|
|
|
|
1.530 |
|
|
|
|
|
|
|
|
|
|
| B3PW91 |
|
1.527 |
1.527 |
1.529 |
1.525 |
1.524 |
1.526 |
1.522 |
1.523 |
1.524 |
|
|
1.523 |
1.521 |
1.525 |
| mPW1PW91 |
|
1.525 |
1.525 |
1.526 |
1.522 |
1.522 |
1.523 |
1.520 |
1.520 |
1.522 |
|
|
1.520 |
1.518 |
1.522 |
| M06-2X |
|
|
|
|
1.525 |
|
|
|
|
|
|
|
|
|
|
| PBEPBE |
|
1.533 |
1.533 |
1.534 |
1.530 |
1.530 |
1.532 |
1.528 |
1.529 |
0.975 |
|
|
1.528 |
1.527 |
1.531 |
| PBEPBEultrafine |
|
|
|
|
1.530 |
|
|
|
|
|
|
|
|
|
|
| Moller Plesset perturbation |
MP2FC |
|
1.539 |
1.539 |
1.543 |
1.523 |
1.521 |
1.524 |
1.523 |
1.524 |
1.522 |
|
1.521 |
1.526 |
1.519 |
1.531 |
| MP2FU |
|
1.539 |
1.539 |
1.542 |
1.521 |
1.520 |
1.522 |
1.521 |
1.522 |
1.517 |
|
|
1.525 |
1.513 |
|
| MP3 |
|
|
|
|
1.525 |
|
|
|
|
|
|
|
|
|
|
| B2PLYP |
|
|
|
|
1.528 |
|
1.529 |
|
|
|
|
|
|
|
|
| Configuration interaction |
CID |
|
1.535 |
1.535 |
1.537 |
1.520 |
|
|
1.520 |
1.521 |
|
|
|
|
|
|
| CISD |
|
1.536 |
1.536 |
1.537 |
1.520 |
|
|
1.520 |
1.521 |
|
|
|
|
|
|
| Quadratic configuration interaction |
QCISD |
|
1.544 |
|
|
1.526 |
|
|
|
|
|
|
|
1.531 |
|
|
| Coupled Cluster |
CCD |
|
1.543 |
|
|
1.526 |
|
|
|
|
|
|
|
1.530 |
|
|
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 |
1.547 |
|
1.543 |
|
1.539 |
1.539 |
| density functional |
B1B95 |
1.544 |
1.537 |
|
|
|
|
| B3LYP |
1.554 |
|
1.550 |
|
1.542 |
1.543 |
| Moller Plesset perturbation |
MP2FC |
1.568 |
|
1.561 |
|
1.560 |
1.560 |
Values that are outliers may reflect different atom numbering for
different levels of theory.
Please use the error
report form to report problems.
