Probability of Finding Oppositely Charged Ions near Each Other

Probability of Finding Oppositely Charged Ions near Each Other 

Consider a spherical shell of thickness dr and of radius r from a reference positive ion (Fig. 3.42). The probability that a negative ion is in the spherical shell is 

A similar equation is valid for the probability of finding a positive ion in a rfr-thick shell at a radius r from a reference negative ion. Hence, in general, one may write for 

This probability of finding an ion of one type of charge near an ion of the opposite charge varies in an interesting way with distance (Fig. 3.43). For small values of r, the function is dominated by rather than by r, md under these conditions P, 

Number of Ions in Spherical Shells at Various Distances 

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