After a post-doctoral year with F. A. Cotton at Texas A&M University, supported by a Liebig Fellowship, he completed his habilitation for inorganic chemistry in 1982 ("Coordination Chemistry of Reduced Heterocycles").
After a post-doctoral year with F. A. Cotton at Texas A&M University, supported by a stipend from the Foundation of the German Chemical Industry, Kaim returned to Frankfurt to start his independent research career. He completed his habilitation for inorganic chemistry in 1982 ("Coordination Chemistry of Reduced Heterocycles").