Keywords: 
• 团簇粒子 /
• 缪勒矩阵 /
• Bruggeman有效介质理论 /
• 离散偶极子近似方法

Abstract: The effects of impurity on the Mueller matrices of randomly distributed cluster agglomerates are analyzed.The equivalent complex refractive indees of silicate particle containing different volume fractions of amorphous carbon are obtained by the Bruggeman effective medium theory.Mueller-matrix elements of randomly distributed cluster agglomerates containing various chemical compositions are calculated by the discrete dipole approximation （DDA） method,and the profiles of Mueller-matrix elements are presented.The influence of the impurity on the Mueller matrices of randomly distributed cluster agglomerates is discussed.The results show that the influence of impurity on the Mueller matrices of randomly distributed cluster agglomerates is quite large,and it varies with the size parameters of the randomly distributed cluster agglomerates.