In the late 1940s, he established a semi-industrial facility separating oxygen isotopes in water, on the Weizmann Institute's campus. It produced water enriched with the heavy oxygen isotope (heavy-oxygen water and more commonly known as heavy water but not to be confused with the more common heavy water with Hydrogen atoms replaced with 2 Deuterium atoms) commonly used in medical diagnostic procedures. He conducted research in several areas and was mentor to generations of young scientists