Group VIIA intermediates

The photochemically studied group VIIA dimers are mainly the Mj(CO),o complexes and their derivatives which contain unbridged, single metal-metal bonds. As with the group VIA dimers, flash photolysis and kinetic studies argue for an additional photoproduced intermediate besides the expected M(CO)j radicals, but the radical species still dominate the photochemistry of these compounds. ... 

The major species in this group are the (h -CjHjjjMjCCO) complexes (M = Fe, Ru). The Os analogue is unexamined. As with the group VIA and group VIIA dimers, two intermediates are produced upon photolysis a short-lived, expected mononuclear -radical and a longer-lived, dinuclear CO-loss product. As with other metal-metal... 

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