χ(3) components of single-crystalline vanadyl phthalocyanine film

Abstract
Single‐crystalline vanadyl phthalocyanine film has been grown by the molecular‐beam epitaxy technique. The χ(3) components, χ111 and χ1111, have been determined by third‐harmonic generation using a fundamental Nd:YAG laser source. The relation, χ1221∼0.8χ1111, reveals that the nondiagonal component significantly contributes to the nonlinear optical response, which originates in two‐dimensional π‐electron system of this molecule.