New molecular compounds of the layer lattice type. IV. New molecular compounds of boron nitride

Abstract

Conclusions, arising from theoretical treatment of data obtained for graphite, indicated that the formation of intercalation compounds should also be possible with other crystalline materials possessing accessible intracrystalline space and the capacity for electronic interaction with intercalated substances. Crystalline boron nitride, which is notable as a structural analogue of graphite, was selected as one of the materials with which to test this hypothesis. Electronic interaction between boron nitride and intercalated substances appeared possible by means of either (i) electron transfer involving normally latent fourth sp3 boron bonds, or (ii) coordination of intercalated cations by unshared pairs of nitrogen valence electrons. The experimental results confirmed these conclusions. Failure to intercalate boron trifluoride and boron trichloride in boron nitride suggests that the unshared pairs of nitrogen valence electrons are partially conjugated in the boron nitride planes.    Results of this investigation strongly favour the view that molecular intercalation shown by graphite is a general phenomenon, likely to occur with any other crystalline substance which satisfies the two necessary conditions noted earlier.