ORIGIN OF 2ND-HARMONIC GENERATION IN VACUUM-EVAPORATED COPPER PHTHALOCYANINE FILM

In situ observation of second-harmonic generation (SHG) was made as a function of film thickness of centrosymmetric copper phthalocyanine du ring the evaporation process. In order to clarify the origin of the re latively strong SHG, the experimental results were compared with calcu lations based on the electric dipole, electric quadrupole and magnetic dipole mechanisms. The comparison clearly ruled out dipolar origin an d strongly indicates electric quadrupolar or, more preferably, magneti c dipolar origin.