Triboluminescence of inorganic lanthanide salts

Abstract

The chapter is devoted to experimental studies on luminescence arising at the mechanical impacts on the inorganic salts of trivalent lanthanides. Triboluminescence spectra are considered. These have two main parts, which correspond to the gas-phase and solid-state components. The mechanisms of their generation are discussed. Some experimental results concerning the mechanisms glow arising at sonotriboluminescence and sonocrystalloluminescence are provided. Thus, at triboluminescence, the intensities of both gas-phase and solid-state components grow under the supplying the inert gases. Besides, the lines of these entered gases are observed in addition to the nitrogen luminescence (this is the only contribution to the gas-phase component of the triboluminescence spectrum on air). The effects of quenching the triboluminescence of the lanthanide salts by a series of polyatomic gases (O2, CO2, and SO2) and sodium nitrite have been elucidated. The mechanisms of these phenomena are discussed. Additionally, the experimental results on the identification based on the triboluminescence spectra of the electronically excited states of the products (OH*, OD*, and O*) have been considered. These species result from mechanochemical decomposition of water molecules of the crystallohydrates and molecular oxygen.