I Dear Suman, You have two different type of charge analysis. One is simple: to get the charge distribution. The second one is to get the charge transfer from/to your system.
In the first case, your system is only one. In this case, you calculate the charge distribution (using one or different schemes) and you are set. In the second case, your system has an initial conformation/configuration, them it suffers some modification giving it a final conformation/configuration. In this case, you calculate the charge distribution BEFORE the fenomenum that alter the conformation/configuration and calculate again AFTER the fenomenum, so, you calculate the charges twice. After that, you calculate the charge transfer as the difference between the two situations. An example: the water molecule. If you one to get the charges in each atom, you calculate the charge distribution for the atoms in the molecule only one time. If you want to calculate the charge modification in the O (the difference between the isolated and molecular atoms) you must do the calculation twice: one for the isolated atom and one for the molecular atom. Then, you calculate the "transferred" charge as Charge_O_isolated-Charge_O_molecular. Regards On 15 Aug, 2014 1:22 AM, "Suman Chowdhury" <[email protected]> wrote: > Dear Camps, > Twice means? Can you please explain clearly what should be the process. > > > On Fri, Aug 15, 2014 at 3:23 AM, Bishal Bhattarai < > [email protected]> wrote: > >> Can we get the wave functions out from the MULIKEN charge distribution ? >> I want to calculate IPR( Inverse Participation Ratio ) for my 648 silica >> atoms >> >> Bishal >> >> >> On Thu, Aug 14, 2014 at 4:11 PM, I. Camps <[email protected]> wrote: >> >>> Hello Suman, >>> >>> If you want to calculate charge transfer you have to do your calculation >>> twice and then calculate the difference of charges for the two >>> calculations. You can use the diferente charge scheme implemented in >>> SIESTA such as Voroni, Hirsfeld or Muliken (or all at the same time). >>> Take a look in the manual for the wright keywords. >>> >>> Regards, >>> On 14 Aug, 2014 6:50 AM, "Suman Chowdhury" <[email protected]> >>> wrote: >>> >>>> Dear siesta user, >>>> How I can estimate the charge transfer from atom to atom from SIESTA? >>>> >>>> -- >>>> >>>> >>>> >>>> *Junior research fellow Dept. of Physics, University of >>>> Calcutta Kolkata- 700009, West Bengal, India.* >>>> * Ph no-+91-9830512232 <%2B91-9830512232>* >>>> >>>> >> > > > -- > > > > *Junior research fellow Dept. of Physics, University of Calcutta Kolkata- > 700009, West Bengal, India.* > * Ph no-+91-9830512232 <%2B91-9830512232>* > >
