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Melting Points and Boiling Points for the Alkali Metals



Nikhila Narayana, Donald R. Burgess Jr.


In this work, we compiled, evaluated, and select recommended values for use for the melting points and boiling points of the alkali metals: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). Here we provide all of the measurements in the literature for melting points and boiling points of these elements along with selection of recommended values. We also compiled and evaluated vapor pressures for (just) lithium from and fitted these set of data from which the boiling point can be accurately determined and computed an enthalpy of vaporization. For values reported prior to 1990, we corrected the values to the International Temperature Scale of 1990 (ITS-90).
Technical Note (NIST TN) - 2273
Report Number


alkali metals, melting points, boiling points, vapor pressure, critically evaluated data


Narayana, N. and Burgess Jr., D. (2024), Melting Points and Boiling Points for the Alkali Metals, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed April 23, 2024)
Created February 29, 2024