Other Alkali Metals include Hydrogen (technically not a metal), Lithium, Sodium, Potassium, Rubidium, and Cesium.
其它碱金属包括氢(技术上说不是种金属)，锂，钠，钾，铷，铯。
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Cesium, rubidium or other alkali metal atoms with simple energy level structure often are used in experiments to study the interaction between light and atoms.