Prof. Mendel Cohen was a member of the Chemistry Department at theWeizmann Institute in
Rehovoth, Israel. He and his group were pioneers in the field of solid state isomerization in organic materials. In 1980, he invited me to give a series of lectures at the Institute on electronic processes in conjugated organic crystals.
Shortly after my visit to the Weizman Institute, I was invited by Professor El Sayed to present a course in Alexandria, Egypt on electronic processes in organic crystals. Scientists from all over Egypt were in attendance, and the course was well received.