Jack W. Eichinger, Jr.
The Floride State University Tallahassee
Graphical Representation of Electron C~nfigurations
A symbolism combining desirable features from methods in current use is suggested. It offers simplicity and clarity and facilitates the visualization of electron structure. I t is flexible and readily adapted to show any amount of detail necessary for a particular discussion. The number of electrons in each main electron shell is listed horizontally. When additional detail is desired for any particular shell, circles may be used to represent orbitals and arrows for electrons as shown in the following examples. conveys all of'the necessary information more graphically than the customary representation (IsZ 2s' 2ps 3sZ3p6 3d1° 4s2 4p6 4d10 4f14 58%5p6 5d1° 6s2 GpZ)and emphasizes the unpaired electrons with parallel spins in the Gp subshell. The upper circle represents the 6s orbital occupied by a pair of electrons spinning in opposite directions. When details involving d orbitals are required, five circles are added below the three which represented the p orbitals. The electron configuration of iron may be shown in the following way.
which graphically presents the important details of the 3d subshell while using numbers to represent electrons in filled shells and subshells. Applying this method of representation to a transuranium element, all of the important features of the electron structure of americium are indicated by
which clearly shows the seven uupaired electrons in the 5f suhshell. I t is sometimes convenient to substitute other symbols for the circles and arrows. I n typewritten copy, the electron structure of iron may he indicated as
with the letters N and V representing orbitals containing paired and single electrons, respectively. These particular letters were selected because their shapes suggest double and single arrows. When unoccupied orbitals are important, they can be iudicated as shown in the following representation of niobium: 2
dVb; 2, 8, 18,G ,I VWVO
Volume 36, Number 6, June 1959
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