3RD-ORDER NONLINEAR-OPTICAL PROPERTIES OF SOLUBLE METALLOTRIAZOLOHEMIPORPHYRAZINES

Soluble lipophilic-substituted metallotriazolohemiporphyrazines (MThp), structurally related to metallophthalocyanines, have been synthesized for the first time. The real part of their third-order molecular hyperpolarizabilities gamma has been determined by third-harmonic generation in chloroform solutions. Two fundamental wavelengths (lambda = 1340 and 1904 nm) have been used to investigate the dispersive behavior of gamma. Values between 10(-34) and 10(-33) esu have been found, depending on excitation wavelength and metal substitution. In fact, unfilled d-shell transition ions markedly enhance the molecular hyperpolarizability, the highest values being measured for the Fe2+- and Co2+-substituted molecules.