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Atomic shells according to ionization energies
1Retired professor of SUNY Erie, PO Box 94, Clarence Center, NY, 14032, USA. dzadeh2010@gmail.com.
Abstract:
This article relies only on experimental data rather than getting involved with theories, calculations, approximations, or interpolations. Experimental ionization energies of all atoms in the periodic table are collected and utilized to discover the order of electronic shells. The assumption in this paper is mainly the energy difference between atomic shells. In other words, one should observe an abrupt change in the energy moving from one atomic shell to another. Electronic energies within an atom are either kinetic or potential. Potential energy can be further broken into "electron-nucleus attraction" and "electron-electron repulsion" energies. The ionization energy that holds an electron onto an atom is equal to the balance of electronic energies. Electronic energies should show jumps and drops when moving from one atomic shell to another and ionization energy is the only part of total energy that can be obtained experimentally. Hence, the variations of experimental ionization energies between consecutive electrons were utilized to investigate the order of atomic shells. The variations of ionization energy were drawn versus the electron numbers to find abrupt changes in the energy, which are so-called "peaks". Then the observed peaks in the graphs were recorded as evidence for the order of atomic shells. The observed order of peaks did not completely match and support the order of atomic shells given by the well-known aufbau (or Madelung) rule. Thus, the observation is reported and a consistent view of the periodic table according to the new order is presented.
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