Photocrystallography of [Ru(bpy)2(dmso)2]2+ reveals an O-bonded metastable state

We report the first instance of observing the phototriggered isomerization of dmso ligands on a bis sulfoxide complex, [Ru(bpy)(2)(dmso)(2)], in the crystalline solid state. The solid-state UV-vis spectrum of the crystal demonstrates an increase in optical density around 550 nm after irradiation, which is consistent with the solution isomerization results. Digital images of the crystal before and after irradiation display a notable color change (pale orange to red) and cleavage occurs along planes, (101) and (100), during irradiation. Single crystal X-ray diffraction data also confirms that isomerization is occurring throughout the lattice and a structure that contains a mix of the S,S and O,O/S,O isomer was attained from a crystal irradiated ex situ. In situ irradiation XRD studies reveal that the percentage of the O-bonded isomer increases as a function of 405 nm exposure time.

Automated summary

We report the first observation of phototriggered isomerization of dmso ligands on a bis sulfoxide complex, [Ru(bpy)(2)(dmso)(2)], in the crystalline solid state. The UV-vis spectrum of the crystal shows an increase in optical density around 550 nm after irradiation, consistent with solution isomerization results. Digital images of the crystal before and after irradiation exhibit a noticeable color change (pale orange to red) and cleavage occurs along planes (101) and (100) during irradiation. Single crystal X-ray diffraction data confirms isomerization throughout the lattice, with a structure containing a mix of S,S and O,O/S,O isomers obtained from a crystal irradiated ex situ. In situ irradiation XRD studies show an increase in the percentage of the O-bonded isomer with increasing 405 nm exposure time.