能级 B→ uze+1 uZe E 2h2n22n2(n1+1+1)2 Z2e21 2a n o aZ a=e/nc能级 e c n c Z a n Z e n l Z e n Z e E r n    , / 1 2 1 1 2 ( 1) 1 2 1 2 2 2 2 2 2 2 2 2 2 2 2 4 2 2 2 4 = − = = − + + = − = − →      