[Pw_forum] Excitation of inorganic materials

Dear QE users and developers, I was wondering if you could elaborate on possibility of modeling absorption spectra of inorganic materials/molecules using TDDFPT module of QE. There are many discussion regarding insufficiency of TDDFT itself to model charge transfer and corresponding issues

[Pw_forum] Color centers and charge states

Dear all, I have recently looked into color centers in ionic solids and I was wondering if someone is familiar with a "reliable approach" to get the charge states right? By that I mean the localization of a charge in let's say Cl defective NaCl should have acquired an excess charge but judging

Re: [Pw_forum] Color centers and charge states

My first choice would be some self-interaction corrected functional - for this case special case something like this below (i.e. a perdew zunger SIC functional only on the excess charge) could be the simplest (it used to be implemented in CP):

[Pw_forum] Plotting phonon dispersion

Hello all, I am using ph.x to get the phonon frequencies and dynamical matrices for an epw.x calculation, however, I would like to plot my phonon dispersions from the ph.x calculation for far, as for example is shown in http://epw.org.uk/Documentation/B-dopedDiamond I am lost as to how I

Re: [Pw_forum] Plotting phonon dispersion

Once you get all the .dyn files from the ph.x run, use the following input to q2r.x to get the force constants: fildyn=’Si.dyn', zasr='simple', flfrc=’Si.ifc2’ / Then use the following input to matdyn.x: asr='simple', amass(1)= 28.0855 flfrc=’Si.ifc2', flfrq=’Si.freq',

Re: [Pw_forum] Plotting phonon dispersion

Thank you Vahid Askarpour. I have two questions: a) Is there a problem if I don't specify amass? b) I have already done this procedure using the following files: ph.x: prefix = 'Si', epsil= .false., fildyn = 'diam.dyn', ldisp= .true. fildvscf = 'dvscf' nq1=6,

Re: [Pw_forum] Plotting phonon dispersion

a) If you skip amass, I think the codes use the mass in the previous runs. b) Did you use ibrav=0 in the scf run? The high-symmetry points you defined are for ibrav=2. Otherwise, just specify the coordinates explicitly. Cheers, Vahid > On Feb 19, 2018, at 9:29 AM, elch...@auth.gr wrote: > >

Re: [Pw_forum] Plotting phonon dispersion

Dear Eleni, Did you use ibrav=0? If so, then you need to use q_in_band_form=.false. q_in_cryst_coord=.true. You can get the path using Xcrysden Best, Saif Ullah Departamento de Física Instituto de Ciências Exatas - ICE Universidade Federal de Juiz de Fora - UFJF Juiz de Fora - MG - Brazil -

Re: [Pw_forum] Plotting phonon dispersion

>Wrong ibrav > > Is it possible that this is because I messed up the names of the > files, or do I need to include explicitly the coordinates of the high > symmetry points? > Well, what's your value of ibrav anyway? Using ibrav=0 would not work, other special values may not work

Re: [Pw_forum] Plotting phonon dispersion

Thank you. That makes sense. Eleni Quoting Vahid Askarpour : > a) If you skip amass, I think the codes use the mass in the previous runs. > > b) Did you use ibrav=0 in the scf run? The high-symmetry points you > defined are for ibrav=2. Otherwise, just specify the

Re: [Pw_forum] Plotting phonon dispersion

On 02/19/2018 03:14 PM, Saif Ullah wrote: > Dear Eleni, > > Did you use ibrav=0? If so, then you need to use q_in_band_form=.false. > q_in_cryst_coord=.true. > Neither of these two bits of advice is correct: 1. q_in_band_form can be used with ibrav=0 as usual, and works just as well as long

Re: [Pw_forum] Plotting phonon dispersion

Ok, I am confused again. I used ibrav=0 in the scf run that eventually gave me the error in matdyn.x. I am running it again. This time I've used, - ibrav = 6, celldm(1) = [..] celldm(3) = [..] -- in the scf. It's good to know if this is more possible to work as

Re: [Pw_forum] Plotting phonon dispersion

1. You could use the ibrav=0 results. In the matdyn.in, do not use gG 50 X 50 M 50 gG 8 Instead, explicitly give the coordinates of each high-symmetry point in cartesian. 2. Four days sounds like a long time unless you are running on few nodes. If a run takes several days, you can break it

Re: [Pw_forum] Plotting phonon dispersion

On 02/19/2018 07:27 PM, elch...@auth.gr wrote: > in the scf. It's good to know if this is more possible to work as ph.x > takes about 4 days. No point in doing all the calculation again.. just use the coordinates of the points for god's sake. With ibrav=4, Gamma is 0,0,0, X is 1/2,0,0, and M is

Re: [Pw_forum] Color centers and charge states

Dear Nicola, thank you for your comment, this was very helpful to get me started! Best, Chris -- Postdoctoral Researcher Center for Quantum Nanoscience, Institute for Basic Science Ewha Womans University, Seoul, South Korea ___ Pw_forum mailing list