Finally, the importance of the electronic structure and the conditions necessary
for photochemical linkage isomerism have been thoroughly investigated in metalnitrosyl systems [22], and much of this insight is thought to be transferable to other
small ambidentate ligands such as nitrite and sulphur dioxide.
Fig. 4 Ground- and excited-state structures of [Pd(Bu 4 dien)(NO 2 )]BPh 4 at 100 K. (a) Structure of
the ground-state nitro (η
1
-NO 2 ) isomer. (b) Structure of the 100% converted excited-state endonitrito (η
1
-ONO) isomer obtained after irradiation at 400 nm for 1 h. Adapted from Ref. [15] under
the Creative Commons Attribution license
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