用定量会聚束电子衍射技术对二十面体AlPdMn准晶结构的优化

对n0，n1，b1和d0等4个位置上的7个原子面，用位置对称性允许的面谐函数描述原子面边界的形状和大小，用定量会聚束电子衍射技术对描述这7个原子面的形状与大小的15个参数进行了精修，得到了一个新的描述二十面体AlPdMn准晶结构的高维空间模型．由这个模型，在三维物理空间用切割法得到了比不考虑棱边中点d0处原子面的球形模型和非球形模型更加完整的原子结构，原子间距不合理的情况得以消除．通过解析式表述的这一模型，与用菱形多面体和91个参数描述原子面的6维团簇模型相比适用性更强．

Refinement of Icosahedral AlPdMn Quasicrystal Structure by Using Quantitative Convergent Beam Electron Diffraction

The 15 parameters,which were used in describing the shape and size of 7 atomic surfaces located at n0,n1,bc1 and ec0 with site-symmetry adapted surface harmonics,were refined by using quantitative convergent-beam electron diffraction technique,and a new high-dimensional model of icosahedral AlPdMn quasicrystal was obtained.With this new model and cut method,the atomic structure of icosahedral AlPdMn quasicrystal in 3-dimensional physical space was obtained.Comparing with other models in which the atomic surface at d0 is not taken into account,it shows more integrated shell structure.And the model given analytically can be applied mor extensively comparing with the 6-dimensional model in which 91 parameters are used in describing atomic surfaces.