1. Single points  Opt, Freq  Single points

3. Basis set HF/3-21G HF/6-31G(d) HF/6-31G(d,p) HF/6-311++G(3df,2p) Collect the electronic energies

4. Correlation Methods HF/3-21G MP2/3-21G MP3/3-21G MP4/3-21G QCISD/3-21G QCISD(T)/3-21G Collect the electronic energies from output files.

5. Opt C 2 H 5 OH design –Gaussview –Gaussian Gaussview HF/6-31G(d) Comparision energy from Single point calcs. with optimised electronic energy

6. Frequency

7. Absorption (i)vertical (or Frank-Condon) excitation (ii)0 - 0’ (or adiabatic) excitation UV-VIS IR

8. Translations (a) and rotations (b) of H 2 O. The normal vibrations of the H 2 O molecule. The fundamental frequencies of the three modes of motions are denoted as ,  (symm

9. Three types of potentials associated with three types of internal modes of motion. Overlapping frequency ranges for stretching, bending and torsional modes of vibration. In general, the 3n-6 vibrational modes can be subdivided into three types of deformations: stretch, bend and torsion (see for example Figures 1.6 and 1.11). The approximate potential energy functions associated with these three types of modes of motion are shown, again schematically, The energy requirement is the greatest for the stretch and the smallest for the torsion. Therefore, these three types fall into three different frequency ranges, even though there is some overlap

10. Six fundamental vibrations of formaldehyde.

11. Characteristic stretching and bending frequencies of the most frequently occurring functional groups are shown in Table 13.3. The torsional frequencies (included in Table 13.3) are usually below 100cm-1.

12. Design of the Transition State C 2 H 5 OH

13. Frequencies of TS

14. Energy difference E TS – E eq

15. Reaction enthalpy Products: H 2 O and C 2 H 4

16. Conformation analysis