Madelung Constant: Definition & Explanation

Thread starter Petar Mali
Start date Aug 18, 2009
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The Madelung constant is defined as A = ±∑(1/p_ij), where p_ij represents the distances between ions in a crystal lattice. The discussion raises a potential issue with the equation A + X = -(A - X) or -A = A, suggesting that it may lead to contradictions unless A is set to zero. Participants express confusion about the implications of this equation and its validity in certain contexts. The conversation highlights the complexities in understanding the Madelung constant and its mathematical relationships. Clarifying these relationships is essential for accurate applications in crystallography and solid-state physics.

Aug 18, 2009

Petar Mali

Madelung constant is define like

A=\pm\sum_j\frac{1}{p_{ij}}

So I can always sayA+X=-(A-X) or -A=A

Can I sometimes problem with this?

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Aug 21, 2009

olgranpappy

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Petar Mali said:

Madelung constant is define like

A=\pm\sum_j\frac{1}{p_{ij}}

So I can always say

A+X=-(A-X) or -A=A

Can I sometimes problem with this?

There seems to be a problem... unless you want A=0.

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