Photochemical behaviour of metal complexes. Pressure effect versus mechanism

imilar expression

can be written for the qua parent activation volume based on quarat

to:

scence q$. according

hv ‘--+

i57 Tabie i Volumes of activation for the reaction [2,3] ~)~s3+f x”-

X

s a

b

-5.2+0.4

+ 12.7+I.2 i-9.5* i.6 +4.2+0.9 -I-6.3L-0.9 444~0.9 -i-%.6&0.6 -b3.4kO.5 +3.7+0.5 -I-0.3f0.1

-4.2kO.5 -4.6+0.7 -7.89 1.8 -10.3& 1.2 -9.%f 1.5 -2.7&O.% ’ assumed value.

dVf"(k,)

AV#(r - ‘) a

b

(-3.4y 3.5+ 1.1 -0.3&O.% + 1.3kO.2

-8.6+ 1.6 --7.7f 1.6 -4-s+ 1.1

-it-i

-8.9+2.7 -6.8f 1.6 -5.3* 1.8

--i-9.3+4.9 -k-6.0&-2.2 4-3.95 1.3 d-7.6+ 1.1 -I-3.3+1.8 d-8.1k1.2 +7.5+ 1.i -t-3.9&0.5 -61.%&0.9

(+3.5)" -1-4.1kO.6

-3.9kO.6

(- 2.6)' -2.6& 6.0 0.2~0.5 0.7kO.3 -i&i (+2.5Y -1-2.521.2 w 0" 0'

20

Cr 0 w

Mm3 Q.QB35 Q.QH28 0.135 0.0135 0.135

366

545 366 545

0.55 0.1 la 0.056 0.01 Qb 0. Q.

-r-9.6+ a-2.7-(-0.3 4-6.Q~Q.2 -“13.3f1.2 f 82~0.5 - 12.Of0.7

LB

161

x

x

H

s

hv

Fig. 7. Plots of In# versus pressure for the reaction [Xl] Fe(CN).#W-

-kS-+Fe(CN),SZ-

-l-NO.

436 313 436 313 436 405 313 a values

at ambient

pressure,

0.17 0.37 0.39 0.63 0.33 0.39 0.42 i.e. 0-B

+7.7+0.4 +s.s~Q.7 +7.2+0.5 44.5 fQ.8 -f-7.9+0.3 +7.5+ 1.1 i-8.4f I.3

+7.8*1.O -5 60.3+0.6

s

s = sohm

s