The specific heats of potassium, rubidium and caesium at temperatures below 330° K

The specific heats of potassium, rubidium and caesium have been measured within the temperature range ~ 20 to 330° K. As in the previously reported case of sodium, anomalies have been found in the specific heats of all these metals. The anomaly in rubidium is found to be affected by heat treatment of the sample. The caesium measurements give direct calorimetric information relating to the caesium-oxygen binary system.