The text is recommended for undergraduate students of organic chemistry who wish to be acquainted with the basics of the Huckel molecular orbital theory.

The aim of these notes is to provtde a summary and concise introduction to elementary molecular orbital theory, with an emphasis on semiempirical methods.

Almost the entire class of molecules of real biological interest is simply out of the question. In general, the theoretician is reduced to model systems of variable appositeness in most of these fields.

The book can prove useful for graduate or advanced students and academicians in the field of general and applied physics.