3RD-ORDER NONLINEAR-OPTICAL PROPERTIES OF SOLUBLE METALLOTRIAZOLOHEMIPORPHYRAZINES

Soluble lipophilic-substituted metallotriazolohemiporphyrazines (MThp) , structurally related to metallophthalocyanines, have been synthesize d for the first time. The real part of their third-order molecular hyp erpolarizabilities gamma has been determined by third-harmonic generat ion in chloroform solutions. Two fundamental wavelengths (lambda = 134 0 and 1904 nm) have been used to investigate the dispersive behavior o f gamma. Values between 10(-34) and 10(-33) esu have been found, depen ding on excitation wavelength and metal substitution. In fact, unfille d d-shell transition ions markedly enhance the molecular hyperpolariza bility, the highest values being measured for the Fe2+- and Co2+-subst ituted molecules.