hi, you can always reduce the grid points...that is for 0 - 20 eV if choose dE=0.05 eV...this will give you 20/0.05 +1 = 401 energy points......this will make the EPSIMG file small.... s.auluck
> Dear Juzar Thingna, > * Thanks !* > * Actually, I have ever tried to calculate the frequency band in > GHz > with the energy ranging from 0 eV to 5 eV. * > *To get the GHz band data, I have to set a smaller BrodenEnergy. The > result > is that I have to accept a larger output * > *file--filename.EPSIMG. Then I input the filename.EPSIMG, I get a larger > e2.dat. Siesta warns that "Too many * > *frequency points". As the high frequencies points are not what I need, I > intercept the low frequencies points as a new e2.dat.* > *With the new e2.dat, I use optical to calculate it and get the results.I > am > not sure the results are right. Is my behavior reasonable ? * > *With so many frequencies points, Siesta completely can't calculate. In > another word, how can we deal with this problem?* > * * > *Best Wishes!* > * * > *Gonerfar > * > 2010/11/8 Juzar Thingna <[email protected]> > >> Hi Gonefar, >> >> The sum rule (its the integral of the dipole strength=total number of >> electrons) is generally a check. >> >> >I have to calculate the energy ranging from 0 eV to 20 eV or much >> higher >> .Then I select the data what I need such as 0 eV ~ 2 eV. Is it right ? >> >> Yes this is correct. >> >> > If I want to calculate much lower frequency band such as GHz or MHz, >> Siesta can't work ? >> >> If your calculation is correct you will get the response of the system >> from >> 0 to 2 eV correctly, which means all frequencies upto 482 THz. >> >> Regards, >> >> Juzar Thingna >> Department of Physics, >> Center for Computation Science and Engineering, >> National University of Singapore. >> >> >> >> >> On Mon, Nov 8, 2010 at 7:15 PM, gonefar Yu <[email protected]> >> wrote: >> >>> Dear Sushil Auluck, >>> Thank you very much! >>> Does it mean Siesta can't calculate the energy ranging from 0 >>> eV >>> to 2 eV? And if I want to get the material's electromagnetic character >>> ranging from 0 eV to 2 eV, I have to calculate the energy ranging from >>> 0 eV >>> to 20 eV or much higher .Then I select the data what I need such as 0 >>> eV ~ 2 >>> eV. Is it right ? >>> Suddenly, another question comes to me. As we know 1 eV equals >>> about 241 THz. If I want to calculate much lower frequency band such as >>> GHz >>> or MHz, Siesta can't work ? >>> >>> Best Wishes! >>> >>> Gonefar >>> 2010/11/8 Sushil Auluck <[email protected]> >>> >>> hi, >>>> increase the max energy to 20 eV or even higher...as you go higher the >>>> sum rule will approach 100%.... >>>> s.auluck >>>> >>>> > Dear All, >>>> > Recently, I was using optical part to calculate the >>>> > graphene's electromagnetic character. I set Optical.EnergyMinimum 0 >>>> eV >>>> and >>>> > Optical.EnergyMaximum 2 eV.However, in the output file it appears >>>> "Fsum >>>> > rule >>>> > is not fulfilled by more than a 20% The dielectric function will be >>>> > extended >>>> > to higher energies by enforcing the Fsum rule This will increase the >>>> > quality >>>> > of the quantities calculated via the Kramers-Kroning relation." Then >>>> the >>>> > result such as reflectance.out, the energy is extended to 0 eV ~ 200 >>>> eV >>>> > while it should be 0 eV ~ 2 eV. As a new user, I am very confused >>>> about >>>> > that. >>>> > I am eager to know how can I avoid the warning and get the >>>> energy >>>> > range what I need such as 0 eV ~ 2 eV. >>>> > Thanks. >>>> > >>>> > Yours >>>> > Gonefar >>>> > >>>> >>>> >>>> ....................................................................... >>>> Prof. Sushil Auluck Phone:+91-512-6797092/6148 >>>> Department of Physics +91-512-6798177(Home) >>>> Indian Institute of Technology Cell :+91-9305548667 >>>> Kanpur 208016 (UP) Fax :+91-512-6790914 >>>> India >>>> E-mail:[email protected]<e-mail%[email protected]> >>>> ...............................................:[email protected] >>>> http://www.iitk.ac.in/phy/People/phy_facvis.html >>>> http://www.iitk.ac.in/phy/New01/profile_SA.html >>>> ....................................................................... >>>> ~ >>>> >>> >>> >> > ....................................................................... Prof. Sushil Auluck Phone:+91-512-6797092/6148 Department of Physics +91-512-6798177(Home) Indian Institute of Technology Cell :+91-9305548667 Kanpur 208016 (UP) Fax :+91-512-6790914 India E-mail:[email protected] ...............................................:[email protected] http://www.iitk.ac.in/phy/People/phy_facvis.html http://www.iitk.ac.in/phy/New01/profile_SA.html ....................................................................... ~
