2010
Volume 10, Number 2, p.p. 74–80
The simplified periodic table: elements ordered by their subshells
Reuben Alper
Cranfield University, Bedfordshire, MK43 0AL, UK
This article introduces a periodic table in which the elements are ordered by the energy level of their subshells and by the number of electrons in their outer shell. This layout makes it easier to understand how the properties of all elements relate to the orbital structure of the atom. The table maintains periodicity, and gives the electron configurations required in modern chemistry but missing from the traditional table. This article also introduces electron “promotion”, which is a simple concept for characterizing the quantum structure of elements that do not conform to the Aufbau principle.