2.晶体结构与空间点阵-A(术语回顾) 晶体( crysta) It is solid. The arrangement of atoms in the crystal is periodIc. 点阵( Lattice) An infinite array of points in space, in which each point has identical surroundings to all others. 晶体结构( Crystal Structure) It can be described by associating each lattice point with a group of atoms called the MOTIF (BASIS) 单位晶胞( Unit Cel1) The smallest component of the crystal, which when stacked together with pure translational repetition reproduces the whole crystal 晶胞参数 Unit Cell dimensions a, b and c are the unit cell edge lengths β and y are the angles( a between b and c,β between c and a, y between a and bc)2. 晶体结构与空间点阵-A（术语回顾） • 晶体(crystal) It is solid.The arrangement of atoms in the crystal is periodic. • 点阵（Lattice） An infinite array of points in space, in which each point has identical surroundings to all others. • 晶体结构（Crystal Structure） It can be described by associating each lattice point with a group of atoms called the MOTIF (BASIS) • 单位晶胞（Unit Cell） The smallest component of the crystal, which when stacked together with pure translational repetition reproduces the whole crystal • 晶胞参数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 .)