Photoelectric and Photochemical Actio//. 



we see that 



r *=^f>^- 



485 



(31) 



j\ t o\v turn to the equation (21) which defines <E>(T). 

 Differentiate both sides bj T and divide each side of the 

 resulting equation by the corresponding side of (21). This 

 gives 



, RT, ™*'(T) 

 w = /w — 5- +K1- 



4>(T) 



• (32) 



J3ut, from equation (2), 



w 



= *(y) -H + 2RT-BT*^, . . (33) 



and since T v is from (29) a function of i/— p only, it follows 

 from (33) that 



0(iO-fo-ffiT + RT*!® +/(*-*o) 



where f{v — v Q ) is an arbitrary function of z^ — z/ only. But/ 

 must be zero because c/> cannot involve v which depends on 

 the properties of a distant surface. Thus 



^) = 7iz,-2RT + RT 2 ||g. . . . (34) 



Substituting the value of F(i/ , v) given by (22) in (10) we 

 have 



(•°° hy 



yfr(v— v o ){0M— liv}e"B>Tdv=0, 



and, from (34), 



r <s>'(T) 1 r°° - — 



{mim - 2RT ) J,, +("-•*>• BT <'"=°- 



Since i|r(v— ^ )^:0, 



pm2<EM T ) _2JIT = 



<£(T) 



(35) 



