【正文】
由于 r*與 r垂直,所以: 由此可得: Hu+Kv+Lw=0 這也就是說,凡是屬于 [uvw]晶帶的晶面,它們的晶面指數(shù)( HKL)都必須符合上式的條件。c* K w a*a* a* 用倒易矢量推導(dǎo)晶面間距和晶面夾角的計(jì)算公式 ? 晶面間距計(jì)算公式 ? 晶面夾角計(jì)算公式 晶面間距計(jì)算公式: 已知 r* = Ha* + Kb* + L c*,則 : 立方晶系: 其它晶系見 P46面。c = c* 1. 晶體具有如下性質(zhì): 剛玉 鄰苯二甲酸氫 鍺酸鉍 電氣石 2. 晶體結(jié)構(gòu)與空間點(diǎn)陣 A(術(shù)語回顧) ? 晶體 (crystal) It is arrangement of atoms in the crystal is periodic. ? 點(diǎn)陣 ( Lattice) An infinite array of points in space, in which each point has identical surroundings to all others. ? 晶體結(jié)構(gòu) ( Crystal Structure) It can be described by associating each lattice point with a group of atoms called the MOTIF (BASIS) ? 單位晶胞( Unit Cell) The smallest ponent of the crystal, which when stacked together with pure translational repetition reproduces the whole crystal ? 晶胞參數(shù) Unit Cell Dimensions a, b and c are the unit cell edge lengths. a, b and g are the angles (a between b and c, b between c and a , g between a and b c .) 晶向和晶面指數(shù) 2. 晶體結(jié)構(gòu)與空間點(diǎn)陣 B ? 等同點(diǎn)與結(jié)點(diǎn) ? 結(jié)構(gòu)基元:原子、分子或其集團(tuán) ? 晶體結(jié)構(gòu)=空間點(diǎn)陣+結(jié)構(gòu)基元 The 14 possib