Triboluminescence of tris(2,2′-bipyridyl)ruthenium(II) dichloride hexahydrate

Abstract

The triboluminescence of tris(2,2′-bipyridyl)ruthenium(II) dichloride hexahydrate complex is detected during the mechanical grinding. The intense lines of N2 in the UV region and a band at 619 nm appeared due to luminescence of [Ru(bpy)3]2+ ion and coincided with the photoluminescence spectrum of the crystals are observed in the emission spectrum in air. The luminescence of N2 is due to electrification of the crystals during the destruction and subsequent discharges in the gas phase. We showed that the luminescence of [Ru(bpy)3]2+ does not occur due to absorption of UV luminescence of N2, because there is only luminescence of the crystal in O2 environment, whereas the luminescence of N2 is completely suppressed. The intense lines coincided with those of Ne and Ar atoms in the electric discharge are observed in the triboluminescence spectra of ruthenium(II) complex in neon and argon environments. In this case, there is an increase in intensity of N2 lines and of a band of [Ru (bpy)3]2+ due to more intense discharges than during the tribodestruction without inert gases. *OH radical is also detected in the triboluminescence spectrum due to mechanochemical decomposition of water molecules in the [Ru(bpy)3]Cl2·6H2O crystalline hydrate.