2.屏蔽效应(续) (1)3d电子能量: 1%K原子电子排布:(1s2)(22p0)(323p)(3n) 3=(1×18)=18.0 Z3n=z-a3t=19-18.0=1.0 E3=-(Z3*2n2)×136=-(12/32)×13.6=-1.5leV >E4=-4.1eV. 对1K:E3>E4 基态19K电子排布为:(2)(2s2p)(323p)(4s) 基态( Ground state)最低能量态;其它能量态都称为“激发态” (Excited state).2. 屏蔽效应（续） （1）3d 电子能量: ◼ 19K原子电子排布: (1s 2 )(2s 22p 6 ) (3s 23p 6 )(3d 1 ) 3d= (1 ×18) = 18.0 Z3d ﹡ = Z - 3d = 19 -18.0 = 1.0 E3d = - (Z3d ﹡2 / n 2 ) ×13.6 = - (12 / 32 ) ×13.6 = -1.51 eV > E4s = -4.1 eV. 对19K ：E3d > E4s ◼  基态19K电子排布为: (1s 2 )(2s 22p 6 ) (3s 23p 6 )(4s 1 ) ◼ 基态(Ground state) — 最低能量态；其它能量态都称为“激发态” （Excited state)