Regularities at the first-order body-centered cubic to face-centered cubic
transition induced by pressure are first shown to relate to the critical th
ermodynamic constants of the five alkali metals from Li to Cs. The melting
transition at atmospheric pressure is then correlated with the critical tem
peratures. Finally, though we recognize that Fr (Z = 87) has a half-life of
only 22 min, predictions are made of its critical constants assuming it to
be a body-centered cubic alkali metal. (C) 2000 Elsevier Science Ltd. All
rights reserved.