Talk:Mod:wearethewalri

Cope Rearrangement

Presentation:

Good use of images. Data tabulated. Captions? Could have made greater use of animations. Some links to original files provided.

Results:

Investigated anti and gauche conformations. Correctly noted gauche 3 as lowest energy isomer and considered vdW interactions and MOs to explain – very good!

Reoptimised anti 2 – Note, you cannot compare energies between different methods (HF and DFT) - they’re calculated on different energy scales. Differences in geometry? Frequency analysis good. IR spectra? Calculations at 0K?

Chair/Boat TS – Results good. IRC calculated for chair using multiple methods – v.good analysis of different methods. Boat?

Activation energies calculated for both levels of theory at 0K and 298K – v.good. Compared to experimental data.

Understanding:

Very good introduction. Could do with conclusion. Steps taken very clear and generally understood. Could do with further reasoning at points as to why certain methods/keywords etc. were used. Very good analysis of results obtained – explaining and rationalising what is seen.

Diels Alder

Presentation:

Data tabulated. Images of structures given. Good use of animations. Use of Jmol?

Results:

MOs of cis-butadiene good. However symmetries incorrectly assigned. MOS for ethylene?

TS – MOs good. HOMO/LUMO interactions covered briefly in legends and diagram, but needs more explanation. Correctly notes C-C bond forming distance is < 2 x vdW radius of C, suggesting bond forming.

Endo/exo: Very thorough. Correctly note endo as lower energy conformation. Additional work calculating IRC for both and activation energies – v.good. Good explanation of HOMO/LUMO interactions here. Delves into kinetic and thermodynamic control. Considers steric effects vs. secondary orbital overlap – and applies this to actual results – Excellent.

Understanding:

Could do with an introduction. Steps taken clear. Further reasoning for these steps/levels of theory/keywords etc. would be useful. Lots of additional work has been carried out to help understand the reaction. Good consideration of endo vs. exo – including discussion of steric reasoning and secondary orbital overlap. These considerations were then applied to the results obtained – v.good. In the conclusion have considered alternative approaches included using solvent in calculations and higher levels of theory.