- What is the problem with unambiguously defining the charge on an atom in a
molecule? - It has been reported that the extended H€uckel method can be parameterized to
give good geometries. Do you think this might be possible for the simple
H€uckel method? Why or why not? - Give the references to a journal paper that used the SHM, and one that used the
EHM, within the last decade. Give an abstract of each paper. - The ionization energies usually used to parameterize the EHM are not ordinary
atomic ionization energies, but rather valence-state atomic orbital ionization
energies (VSAO ionization energies). What does the term “valence state” mean
here? Should the VSAO ionization energies of the orbitals of an atom depend
somewhat on the hybridization of the atom? In what way? - Which should require more empirical parameters: a molecular mechanics force
field (Chapter 3) or an extended H€uckel method program? Explain.
Harder Questions 173