The band spectrum of zirconium oxide

(i) The spectrum of ZrO has been photographed from λ2600 to λ8800, and bands have been found to extend from λ3200 to λ7600. (ii) The most prominent bands have been analysed into three systems, all having the same lower electronic state; the blue system α is probably due to a transition 3Π → 3Π; the yellow system β and the red-infra-red system γ are probably due to transitions 3Σ → 3Π. (iii) Analysis of the remaining bands is in progress.