Light by UasymmetriGal Atoms and Molecules. 395 



With the notation indicated by the figure, the direction 

 cosines of 00 with respect to the fixed axes are 



sin cos i/r, sin 6 sin >/r, cos 6 ; 

 Fiff. 1. 



the direction cosines of OA are 



cos 6 cos yjr cos cj) — sin d> sin ^, 

 cos 6 sin yjr cos ^> -f sin cf> cos yjr, 



— sin # cos c/> ; 



those of OB are 



— cos 6 cos yjr sin <£ — cos (/> sin ijr, 



— cos 6 sin -v|r sin <fi + cos <£ cos ^r } 



sin # sin 0. 



Thus the components of Z along OA, OB, 00 are 



Fx = - Z sin cos 0, F 2 = Z sin (9 sin 0, F 3 = Z cos 0. 



f, r/, f, the displacements of the electron along OA, OB, OC 

 due to these forces, are given by 



,._ Z sin 6 cos <£ _ Z sin sin $ Z cos (9 



*"~""~ A-mjt? 2 ' ?/ ~ B-mp 2 ' *~C-wp 2 * 



2 1) 2 



