Light hy in symmetrical Atoms and Molecules. 403 



From^' = X', 

 ot 



_ r da f dn^\ de 



X = — 7 < n + a-r- ^sin cb — an cos m. 7 

 dt \ da J r * dt 



~ ae 17 ((P~- *L) n h cos i/r — (p + 1) nk 2 cos%). 



dt 



From these and from the equation 



we get 



(Y'sin0 + X'cos<£), 



dt nj) 2 a 



de 1 



-j = {Y^^cos^ + ^cos i|r) + X / (/; 1 sin^ — k 2 s'mx)}, 



The third and fourth of these equations are equivalent to 



1 



nap 



-^ (e cos co) = ~ -{Y'facosx' + hcosTJr') 



■+- X (k l sin ^' — h 2 sin x!) \ , 



j % (e sin a)) = — {Y'(k 2 sin x ' + *i sin ^') 



+ X'(^g cos %' — /fj cos yfr')}, 

 where 



