和透射电镜观察 ,表明银纳米粒子的聚集方式为链状聚集 .当聚集体
平均尺寸为 12 0nm时 ,银纳米粒子聚集体的HRS信号强度
比聚集前增大了约 15倍 .分析表明 ,聚集导致银纳米粒子表面电场极化
The hyper Rayleigh scattering(HRS) technique has been employed to determine the second order nonlinear optical response of a highly monodisperse silver colloid and its aggregation which is induced in the presence of KNO 3. Through the size distribution and TEM measurements,the silver nanoparticle aggregates have been observed as a chain like aggregation. The experimental result reveals that HRS signal increases 15 times when the aggregation average size is up to 120nm.