1. Organic chemistry Use Gaussian to calculate A He for the hydrogenation of ethene to make ethane. Use
Hartree-Fock theory with the basis sets 3-21G, 6-31G(d), and 6-311+G(d,p). Also, obtain the literature
4,H° of each substance from your textbook.
(a) Construct a table of results for all absolute enthalpy H° values (in hartrees) and the four A H°
values in kcal/mol.
(b) With what basis set is chemical accuracy reached?
(c) Is it important to know if the calculated absolute enthalpies H° of each substance reached chemical
(d) Has the complete basis set limit for these calculations been reached? Explain.
4. Selection rules We have spent a lot of time learning about spectroscopic selection rules, such as AJ
for rotation, Av = 1 for vibration, and As = 0 for electron spin. However we did not spend much
time justifying or using the selection rules for electron orbital changes during transitions, though they
certainly exist! For atoms, they are discussed in Atkins 9C, and for molecules in Atkins 13A.
document that teaches fellow physical chemistry students about these electron orbital selection
rules. The maximum size is one side of one printed page of letter-sized paper. It might be best to design
it in Powerpoint for easy use of space, layout, and graphics. You may use smaller fonts as long as the
final printed page is legible. You may do this by hand if it is neat.
Topics you may want to include are transition dipole moments, term symbols, angular momentum
tum numbers, and certain simple types of symmetry.
To be clear, you want to prepare a document that presents essential information so that a fellow student
can understand and appreciate it. It does not need to cover every last detail! You do not want to simply
copy derivations and text from the book! You will need to spend some time reading and digesting the
information in the book before you can decide what is most important and interesting to present to a
These solutions may offer step-by-step problem-solving explanations or good writing examples that include modern styles of formatting and construction
of bibliographies out of text citations and references. Students may use these solutions for personal skill-building and practice.
Unethical use is strictly forbidden.