一组Dawson型多金属氧酸盐和相应的有机-无机杂多化合物的超快非线性光学响应

摘要

通过时间分辨率为115fs的超快光克尔方法测量了多金属氧酸盐K8[P2Mo4W13M(H2O)O61](M=Mn,Co,Ni,Cu,Zn)和相应的有机-无机杂多化合物(C19 H25 N2)7 K3[P2 Mo4 W13 MO62]在830 nm处的三阶非线性光学性质.多金属氧酸盐阴离子和相应的杂多化合物都表现出很大的三阶非线性,其中M=Cu的取代物的非线性系数要比其他小一个数量级.通过比较有机-无机杂多化合物和生成前者的反应物的γ值,发现杂多化合物中的电荷转移效应极大的增强了三阶非线性光学性能.%Thethird-order optical nonlinearities of the polyoxometalates of K8 [P2 Mo4 W13 M (H2 O) O61 ](M =Mn,Co,N i,Cu,Zn) and their organic-inorganic hybrid compounds of (C19H25N2)7 K3 [P2 Mo4 W13MO62]were measured by using ultrafast optical Kerr effect at 830nm wavelength,with time resolution of 115fs.Both of the polyoxometalate anions and the heteropoly compounds exhibited large third-order optical nonlinearity except the copper substituted one,which is one order of magnitude smaller than the others.By comparing the γ values of the organic-inorganic hybrid compounds and that of their reactants,it is concluded that the charge-transfer remarkably enhanced the third-order optical nonlinearities of the hybrid compounds.