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<div><font style="font-family: Tahoma; font-size: 10pt;"> Dear Paolo,</font>
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<div><font style="font-family: Tahoma; font-size: 10pt;"> </font></div>
<div><font style="font-family: Tahoma; font-size: 10pt;">>> That's ok.
Now, suppose we have two bunches of orbitals corresponding<br />
>> to two well separated molecules, "A" and "B".
"A" contains, say, 8<br />
>> electrons and "B" contains 14 electrons. The HOMO of
"B" is higher<br />
>> than the LUMO of "A". Then you mean that the code fill
some unoccupied<br />
>> levels of "A" to make an artificial charged fragments?<br
/>
<br />
> yes. It fills the LUMO of "A" until it is aligned with the
HOMO of "B",<br />
> as explained by SdG in his previous message.<br />
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<div><font style="font-family: Tahoma; font-size: 10pt;"> If the KS
orbitals of "A" and "B" do not overlap, so the
KS-Hamiltonian martix elements containing one orbital from
"A" and another from "B" vanish and the Hamiltonian
decouples in to two separate parts corresponding to "A" and
"B" separately. So, the diagonalization, and density calculations
can be performed separately, isn't it?</font></div>
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<div><font style="font-family: Tahoma; font-size: 10pt;">mahmoud</font></div>
<div><font style="font-family: Tahoma; font-size: 10pt;"> <br />
<br />
<br />
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