倒易点阵(reciprocal lattice) First introduced by Peter Paul Ewald in 1921 b×c cXa axb a*: ,b*= c* V V V b*×c* c*x a* a*×b* a .b= c= V* V* V* a*垂直于bc平面； b*垂直于ac平面； c*垂直于ab平面； b* 11倒易点阵(reciprocal lattice) • First introduced by Peter Paul Ewald in 1921 11 a*垂直于bc平面； b*垂直于ac平面； c*垂直于ab平面；