Photophysics and photochemistry of alkali metal vapors

Abstract

The alkali metals (lithium, sodium, potassium, rubidium and cesium) have a number of unique properties in the gas phase which contribute to their widespread study in basic and applied research. At room temperature, they are metallic solids of high chemical reactivity. At temperatures between 28.5°C (Cs) and 186°C (Li), the solids melt to form liquid metals. At temperatures between 705°C (Cs) and 1317°C (Li), these liquids boil to form alkali metal vapors. It is these vapors we shall focus on here, albeit usually at temperatures below boiling and thus pressures less than one atmosphere.The alkali metals (lithium, sodium, potassium, rubidium and cesium) have a number of unique properties in the gas phase which contribute to their widespread study in basic and applied research. At room temperature, they are metallic solids of high chemical reactivity. At temperatures between 28.5°C (Cs) and 186°C (Li), the solids melt to form liquid metals. At temperatures between 705°C (Cs) and 1317°C (Li), these liquids boil to form alkali metal vapors. It is these vapors we shall focus on here, albeit usually at temperatures below boiling and thus pressures less than one atmosphere.