Andreas von Antropoff his Periodic Table in the article ""Eine neue Form des periodischen Systems der Elemente"" in the "Zeitschrift für angewandte Chemie" in 1926. The periodic table is regularly numbered from 1 - Hydrogen to 118 - Oganesson, with "each number representing the number of protons stored within an atom's nucleus in a satisfying balance" compared to most other contemporary tables. In addition he placed the theoretical "Element zero", which had "been a matter of conjecture for nearly a century" atop his periodic table and called it Neutronium. His periodic table was in widespread use in German schools until 1945 and soon
Alternative periodic tables extended periodic table, suggested by Glenn T. Seaborg in 1969, yet unknown elements are included up to atomic number 218. Theoretical periods above regular period 7 are added. In the research field of superatoms, clusters of atoms have properties of single atoms of another element. It is suggested to extend the periodic table with a second layer to be occupied with these cluster compounds. The latest addition to this multi-story table is the aluminium cluster ion , which behaves like a multivalent germanium atom. Alternative periodic tables Alternative periodic tables are tabulations of chemical elements differing significantly in their organization