Luminescence of Solids at Low Temperatures

Abstract

THE fluorescence of solids has generally been regarded as a comparative rarity confined to a few groups of compounds, of which the sulphides of zinc and calcium, the uranyl salts, and a number of platino-cyanides are amongst the better known. Recent observations at low temperatures suggest that many other compounds are fluorescent, and a fairly wide distribution throughout the periodic table is indicated. Table 1 gives a list of some of the more striking compounds, a number of which are not fluorescent at room temperature. The fluorescence intensity of a few of these compounds is weak even at the temperature of liquid nitrogen ; compounds also showing appreciable fluorescence at room temperatures are indicated in italics.