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运用平面波展开法计算由长方体散射物以面心立方结构排列于基体中形成的三维声子晶体的带结构,研究不同组分材料、散射物的填充率和长方体散射物的高与长之比 R_(HL)对带隙的影响.结果表明,将质量密度和波速大的散射体放在质量密度和波速小的基体中所形成的三维(面心立方)固态声子晶体有利于带隙的产生；散射体的填充率为中间值时带隙最宽；散射体的对称性强烈影响带隙,当 R_(HL)大于等于1时,带隙宽度随 R_(HL)的增加而减小,相反,当 R_(HL)小于1时,带隙宽度随 R_(HL)的增加而增加.
The band structures of the three-dimensional phononic crystals formed by the face-centered cubic structures arranged in the matrix are calculated by using the plane wave expansion method. The relationship between the filling ratio of the different components and the ratio of the height to the length of the scatterers R_ (HL) on the band gap.The results show that the three-dimensional (face-centered cubic) solid phononic crystals formed by the mass density and velocity-fast scatterers in the matrix with small mass density and velocity are favorable to the bandgap generation The bandgap is the widest when the fill rate of the scatterer is the middle value. The symmetry of the scatterer strongly influences the bandgap. When R HL is greater than or equal to 1, the bandgap width decreases as the R HL increases When R HL is less than 1, the band gap width increases with the increase of R HL.