Geometry Optimization Methods
Objective
The objective of this exercise is to compare the optimized molecular geometry predicted
by various computational methods to the experimental molecular geometry.
Procedure
Fill in the following table comparing the C-C bond length (in angstroms) predicted by various
computational methods for several molecules.
|
| Molecule |
Clean-up |
PM3 |
Ab Initio [HF/6-311G+(d,p)] |
Experiment |
| ethane |
|
|
|
1.531 |
| ethene |
|
|
|
1.339 |
| ethyne |
|
|
|
1.203 |
| 1,3-butadiene C1-C2 |
|
|
|
1.345 |
| 1,3-butadiene C2-C3 |
|
|
|
1.483 |
|
Describe each method and comment on its accuracy.
|
Clean-up:
PM3:
Ab Initio:
|
Key
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