ARTICLES 



THE RELATION OF MAGNETISM TO 

 THE CRYSTALLINE STATE 



By MAJOR A. E. OXLEY, R.A.F., M.A., D.Sc, University College, London. 



Introduction. — In recent years important developments of the 

 theory of atomic structure have been made, but it must be 

 admitted that most of these provide a very imperfect means 

 of correlating certain definite facts bearing on the magnetic 

 properties of matter. To take one instance, the Rutherford- 

 Bohr theory of the simpler types of atom ignores magnetic 

 forces completely, and the Bohr hydrogen-molecule is definitely 

 paramagnetic in contradiction to the well-known fact that 

 molecular hydrogen is diamagnetic, possessing a molecular 

 susceptibility — 61 x io -7 . While emphasising this point, 

 it is to be understood that no attempt is here being made to 

 show that an alternative theory based purely on an element of 

 magnetism will give a more satisfactory solution ; rather, that 

 the known magnetic data imply that the more recent theories 

 are inadequate, and require to be supplemented or modified, 

 so that while retaining their present validity, as regards the 

 interpretation of the phenomena which they were devised to 

 explain, due recognition is taken of the available experimental 

 data furnished by recent magnetic researches. It is therefore 

 proposed to examine to what extent the magnetic forces due 

 to orbital electron motions are capable of explaining magnetic 

 phenomena, to regard these effects as superimposed upon the 

 electrostatic effects, and, as far as possible, to ascertain whether 

 in any particular case the electrostatic or electromagnetic 

 forces predominate. 



Experimental. — In a series of memoirs the author ' has 

 attacked this problem. The substances examined consisted of 

 about 40 organic compounds whose! magnetic properties were 



1 Phil. Trans. Roy. Soc, Vol. 214A, p. 109, 1914 (Parts 1 and 2) ; ibid.. 

 Vol. 215A, p. 79, 1915 (Part 3) ; ibid., in course of publication (Part 4). For 

 brevity these memoirs are referred to as Parts 1,2,3 an d 4 in the text. 



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