Structure of the Azide Group

IN the account in Nature of May 26, p. 802, of the recent discussion on dipole moments held at Oxford by the Faraday Society, reference is made to the probable linearity of the arrangement of the nitrogen atoms in the azide group. An X-ray examination of cyanuric triazide made by Miss Knaggs in the Davy Faraday Laboratory shows that this hypothesis is correct. I gave a short account of her work in a lecture at the Royal Institution at the end of last year. The arrangement bears a curious resemblance to the arms of the Isle of Man, a row of three nitrogen atoms lying in the position of each leg from knee to ankle.