Evidence for Energy Regularity in the Mendeleev Periodic Table
  We show that the dependence of the total energy of the atoms on their atomic number follows a q-exponential (function proposed by C. Tsallis), for almost all elements of the periodic table. The result is qualitatively explained in terms of the way the atomic configurations are arranged to minimize energy. 
Cassio H. S. Amador, Liliana S. Zambrano