Dear Prof. Stefano, Thank you for your reply. I did not receive your message on my email that is why I missed it.
When I diagonalize the q dependent matrices I can obtain the eigenvalues (frequencies) from which I am getting the correct phonon dispersion but the frequency range is not correct as I had shown in a figure I previously attached. Even if I multiply now with 13.6 eV (13600 meV) to convert Ryd to meV I am not able to reproduce the frequency range. Could you please suggest what factor I am missing here? Thank you very much. Sincerely, Shubham From: "Stefano de Gironcoli" <[email protected]> To: "Quantum ESPRESSO users Forum" <[email protected]> Sent: Tuesday, April 15, 2025 9:25:04 PM Subject: Re: [QE-users] unit mismatch between PH generated frequencies and manually generated eigenvalues Ryd/au^2 ... as already stated in my previous reply Stefano Get [ https://aka.ms/AAb9ysg | Outlook for Android ] From: users <[email protected]> on behalf of Shubham Patel <[email protected]> Sent: Tuesday, April 15, 2025 5:45:37 PM To: Quantum ESPRESSO users Forum <[email protected]> Subject: Re: [QE-users] unit mismatch between PH generated frequencies and manually generated eigenvalues Hello again, Could anyone please tell? Sincerely, Shubham ----- Original Message ----- From: "Shubham Patel" <[email protected]> To: "Quantum ESPRESSO users Forum" <[email protected]> Sent: Friday, April 11, 2025 3:28:53 PM Subject: Re: [QE-users] unit mismatch between PH generated frequencies and manually generated eigenvalues Hi, Could someone please tell what is the unit of dynamical matrix elements'. I have to do some post processing from the dynamical matrices and therefore I want to know the proper units of the elements. Thank you, Shubham ----- Original Message ----- From: "Shubham Patel" <[email protected]> To: "Quantum ESPRESSO users Forum" <[email protected]> Sent: Wednesday, April 9, 2025 8:09:58 AM Subject: Re: [QE-users] unit mismatch between PH generated frequencies and manually generated eigenvalues Dear Kazume NISHIDATE, Thank you very much for your prompt reply. This is indeed correct what you observed. However, when I divide the y scale of right hand side figure with 0.005 it should return the left figure but it does not. Attaching the modified figure in the right most (dividing with 0.005). Am I missing something? Thank you, Shubham ----- Original Message ----- From: "Kazume NISHIDATE" <[email protected]> To: "Quantum ESPRESSO users Forum" <[email protected]> Sent: Wednesday, April 9, 2025 1:54:59 AM Subject: Re: [QE-users] unit mismatch between PH generated frequencies and manually generated eigenvalues Dear Shubham, I’m not an expert on the phonon calculation. But it may be in a wavelength unit. The bottom of the curve in the left-hand graph is around 25 meV. 25 meV = 0.025 eV 0.025 eV is around 50 micro m (wavelength). [ https://sherwingroup.itst.ucsb.edu/internal/unit-conversion/ | https://sherwingroup.itst.ucsb.edu/internal/unit-conversion/ ] = 50 x 10^(-6) m = 50 x 10^(-6) x 100 cm = 50 x 10^(-4) cm = 5 x 10^(-3) cm = 0.005 cm It is around the bottom of the curve in the right-hand graph. > 2025/04/09 0:03、Shubham Patel <[email protected]>のメール: > > Dear developers and users, > > I am trying to calculate the frequencies (freqs) using Quantum Espresso > PHonon calculations as well as using dynamical matrices generated using > matdyn.x. I find that there is a unit mismatch in the freqs which gives rise > to a magnitude difference. In the first case, I calculate phonon band > structure using matdyn.x --> plotband.x. While in the second case I generate > dynamical matrices using matdyn.x and then diagonalize the matrices along the > kpath and generated exactly same band dispersion except the magnitude on the > y-axis (frequency range). Could anyone please tell what is this factor which > brings the magnitude mismatch? I am also attaching a figure to compare. > > Thank you very much for any help. > > Sincerely, > Shubham<phdos_AZX_mimatch.pdf>__________________________________________________ > 西館数芽 Kazume NISHIDATE Ph.D Department of Systems Innovation Engineering, Graduate School of Science and Engineering, Iwate University 4-3-5 Ueda, Morioka, Iwate, 020-8551 JAPAN Phone:+81-19-621-6391 [email protected], [email protected] [ https://sites.google.com/site/nisidatelab/ | https://sites.google.com/site/nisidatelab/ ] _______________________________________________________________________________ The Quantum ESPRESSO Foundation stands in solidarity with all civilians worldwide who are victims of terrorism, military aggression, and indiscriminate warfare. -------------------------------------------------------------------------------- Quantum ESPRESSO is supported by MaX ( [ http://www.max-centre.eu/ | www.max-centre.eu ] ) users mailing list [email protected] [ https://lists.quantum-espresso.org/mailman/listinfo/users | https://lists.quantum-espresso.org/mailman/listinfo/users ] _______________________________________________________________________________ The Quantum ESPRESSO Foundation stands in solidarity with all civilians worldwide who are victims of terrorism, military aggression, and indiscriminate warfare. -------------------------------------------------------------------------------- Quantum ESPRESSO is supported by MaX ( [ http://www.max-centre.eu/ | www.max-centre.eu ] ) users mailing list [email protected] [ https://lists.quantum-espresso.org/mailman/listinfo/users | https://lists.quantum-espresso.org/mailman/listinfo/users ] _______________________________________________________________________________ The Quantum ESPRESSO Foundation stands in solidarity with all civilians worldwide who are victims of terrorism, military aggression, and indiscriminate warfare. -------------------------------------------------------------------------------- Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list [email protected] https://lists.quantum-espresso.org/mailman/listinfo/users
_______________________________________________________________________________ The Quantum ESPRESSO Foundation stands in solidarity with all civilians worldwide who are victims of terrorism, military aggression, and indiscriminate warfare. -------------------------------------------------------------------------------- Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list [email protected] https://lists.quantum-espresso.org/mailman/listinfo/users
