The semiempirical MIM method was applied to calculate the
UV spectra of nine pyridine-aromatic-ester derivatives (having the
general formula R1-COO-R2) assuming a planar geometry. Benzene,
pyridine and formic acid were adopted as component systems.
The dipole moments of the same compounds were evaluated at the
MIM and INDO levels and the equilibrium percentage of the conformers
was deduced from experimental and theoretical values.
Comparable results were generally obtained. On the whole the
results are satisfactory but not sufficient to affirm with certainty
if the molecular skeleton is or is not planar