Mechanoluminescence of terbium and cerium sulfates in a noble-gas atmosphere

Abstract

Lines of Ne (3p-3s, 550–800 nm) and Xe (6p-6s, 800–1050 nm; 7p-6s, 475 nm) have been detected in the mechanoluminescence spectrum of terbium and cerium sulfate crystallohydrates. The luminescence of noble gas is observed jointly with the known bands of Ce3+ and Tb3+ ions and N*2 lines. The lines corresponding to excited Xe+ ions (500–550 nm), indicative of achievement of electric-field strengths on the order of 107 V/cm during mechanoluminescence, are also observed. It is established that, during mechanoluminescence of Tb2(SO4)3 · 8D2O in an argon atmosphere under a pressure of 1.3 atm, mechanochemical reactions of decomposition of crystallization water (D2O) molecules cause luminescence of OD radicals; this luminescence is initiated by electron impact occurring during electrization and in discharges in crystals during destruction.