Grimm-Sommerfeld rule

To define quickly and exactly if a doped or compound semiconductor containing a fraction y of an impurity B, i.e., A B, is -type or p-type, it is possible to use the following practical rule, called the Grimm-Sommerfeld rule. For this purpose, it is important to introduce the dimensionless physical quantity called the average number of valence electrons, denoted n, and which is calculated by given by the following equation  

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The Grimm-Sommerfeld rule is valid for the bond lengths if the sum of the atomic numbers is the same, the interatomic distances are the same. For example ... 

Klemm proposed designating the charged Xr unit as a pseudoatom (or a set of pseudoatoms) behaving structure-chemically like isoelectronic elements [6-8]. This was an extension of the old Grimm-Sommerfeld-rule for four-electron species [9]. 

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