Vyacheslav
kreme_vg@chemy.kolasc.net.ru
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On Fri Apr 23 '10 0:09am, Andrei V Scherbinin wrote
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>Hello,
>Now it seems more clear for me.
>1. Your negatively charged complex is probably not able to bind as many M+ cations as you wish
>for simple electrostatic reasons. For example, in ionic crystalline solid, the coordination sphere
>may include a lot of counter-ions just because of presence of the Madelung potential of the surrounding lattice. So if your aim is to simulate the condensed phase, you should provide adequate environoment, otherwise it makes little sense.
>2. You use local optimization routines which do not guarantee that you reach the global minimum.
>Moreover, there are no numerical methods allowing to do this with a guarantee. So if you still
>suspect that the problem is in the algorithms you use, you could examine a kind of multi-start
>methodology, i.e., perform a number of local optimization runs starting with different initial
>structures generated manually or randomly.
>However, I think that the real problem is 1. rather than 2.
>Best wishes,
>Andrei
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