Author/Authors :
Yumashev ، نويسنده , , K.V and Malyarevich، نويسنده , , A.M and Posnov، نويسنده , , N.N and Denisov، نويسنده , , I.A and Mikhailov، نويسنده , , V.P and Artemyev، نويسنده , , M.V and Sviridov، نويسنده , , D.V، نويسنده ,
Abstract :
The nonlinear optical properties of UV-coloured colloidal polytungstic acid imbedded in polyvinylalcohol film have been studied using a picosecond pump–probe technique. The intervalence charge transfer bands in the red-near IR region were found to exhibit transient bleaching that decays monoexponentially with the characteristic time of ∼300 ps. The results obtained are discussed in terms of the splitting of energy levels of metal ion in the ligand field and the delocalization of valence states.