On Fri, Jan 25, 2019, emanuele falbo wrote:
>Sorry , I meant that the dynamics fails when the M solute molecule and 15
>Li ions are both treated with semi-empirical PM6, whereas the water at MM
>level .
First: there is (I think) no reason to treat Li+ ions as quantum
mechanical. Are you expecting any electron transfer from the metal?
Second: there is a good reason not to do this: the QM/MM code is
designed for a compact QM region. As I understand it, your Li ions may
move all over the place.
Finally: you are correct in noting that SCF failures can be hard to fix,
especially with a highly negative charge. The Reference Manual has some
suggestions of things to try. But handling metal oxides (as opposed to
organic molecules) may require considerable experimentation.
...good luck...dac
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Received on Sat Jan 26 2019 - 07:30:02 PST
