Talk:Mod:MRTSFN89 phys
Cope Rearrangement
Presentation:
Data clearly tabulated. Good use of images/diagrams. Use of Jmol where appropriate. Animations to show vibrational frequencies. Use of file sharing?
Results:
Investigated almost all of the anti and gauche conformers – v.good. Student has correctly noted gauche 3 as the lowest energy isomer. Would you expect this? An explanation considering vdW interactions, MOs etc would assist the report. Anti conformer was reoptimised and thermochemical data is provided for 298K and 0K – good. IR spectrum?
Chair/boat TS: Results generally v.good. Transition states found and IRC calculations carried out for both using a number of different methods. Activation energies calculated for chair and boat using both levels of theory. The table is a little confusing as the titles within the table don’t apply to the values inside it. Were activation energies calculated at 0K? Converting these values to kcal/mol would have perhaps made it easier to visualise.
Understanding:
Very thorough introduction with good use of primary literature. The student has a good understanding of the levels of theory used and why they have been applied in this study. The student also has a good grasp on the use of keywords and what they instruct the calculation to do. The student has gone beyond what was asked and investigated a potential stepwise reaction.
Diels Alder
Presentation:
As above. Data sometimes not tabulated but hidden in script, making it harder to read.
Results:
MOs of reactants good, correct symmetries noted, and thorough explanation of HOMO/LUMO interactions. TS MOs good – student has given additional thought to the HOMO TS. Correctly noted that the TS shows a bond is partially formed as the C-C distance is < 2 x vdW radius of C.
Endo/exo: Results generally good. Correctly noted endo is lower in energy and explained by considering steric reasoning and the secondary orbital overlap effect. This effect could be explained further, although good use of a diagram has been made. Apply this effect to your results? Is this effect really apparent in your results for the endo? Additional work carrying out the IRC calculations adds individual thought to this report.
Understanding:
Again, a v.thorough introduction explaining what will be covered in this section. The results have been analysed well: The student has a good understanding of HOMO/LUMO interactions and allowed/forbidden reactions and this is explained well with use of diagrams. Also steric interactions for the endo/exo states have been well considered. As mentioned above – student could expand on the secondary orbital overlap effect. Perhaps a little rushed towards the end without a conclusion, but in general this report was very good and extremely thorough.