[cth]

I have a crystal structure of an organic compound which is ionic. So I know the precise positions of all anions and cations within the unit cell.

I am interested in determining the Madelung constant of that compound. Unfortunately, it converges far too slowly and I can't do it by hand. Would you know of a software that allows to calculate that constant ?  How could I calculate it ?

Thank you 

[Borek]

Good reason to learn how to write your own programs.

[h3zz5]

look at the paper by Bakers in J Chem Ed  2010 March Issue - it is on the front cover--all u need is a coordinate file of your compound and their prog will do it --u can get the prog from the supplementary material in their work on the web

[cth]

Thanks a lot for the paper references, I'll dig up some old results and have a new look at them soon.