Rupture luminescence from natural fibers

Fibers of cotton and wool, and samples of paper, have been ruptured in tens ion in vacuum and in air, and give detectable luminescence in the visible r ange. All have a common emission peak at around 2.0 eV, which is ascribed t o the deexcitation of states excited by the rupture of organic chain molecu le bonds. Rubber bands give stronger emission in air, but no emission in va cuum, suggesting the material breaks only at weak interchain bonds. Mohair, cat, and horse hair also give emission in air. The phenomena reveal effect s that would occur widely in nature. (C) 1999 American Institute of Physics . [S0021-9606(99)70245-X].