Abstract
The selectivity of photo-electron transition in the surface of zinc crystal was closely examined, and found that it has an intimate relation with the direction of the oscillating electric vector of the exciting light. Further, applying the results obtained from the electrode potentials of the surfaces of Zn-single crystal, it was inferred that the selection rule, Δ=±1, is explicable from the fact that the stability of orbital motion of the election depends on the mutual orientation of the orbital plane and the electric vector of the exciting light. On the basis of this conception it was concluded that the orbital planes of p and d electrons in the energy levels, E2 and E3, in the surface layer of zinc crystal are perpendicular and parallel, respectively to the axis, [0001], of the crystal of this metal.
