Hi, in the input you use the option crystal_b, which means that your k-points are in crystal coordinates (that is, you give the component along the three reciprocal lattice primitive unit cell vectors).
bands.x i think provides the SAME k-points, but in CARTESIAN coordinates and 2pi/a units. For example: crystal units: x1, x2, x3 Reciprocal lattice vectors: G1, G2, G3 k-point cartesian coordinates: (kx, ky, kz) = x1 G1 + x2 G2 + x3 G3 bands..x prints kx/(2pi/a), ky/(2pi/a), kz/(2pi/a) Giovanni -- Prof. Giovanni Cantele Dipartimento di Fisica "Ettore Pancini" Universita' degli Studi di Napoli "Federico II" Complesso Universitario M. S. Angelo - Ed. 6 Via Cintia, I-80126, Napoli, Italy e-mail: giovanni.cantele@unina Phone: +39 081 676910 Web page: https://sites.google.com/view/giovanni-cantele/home Il giorno dom 28 set 2025 alle ore 15:18 wenusaras <wenusa...@uom.lk> ha scritto: > Dear Vishad, > > Thank you very much for your quick reply. > Could you please provide a bit more detail on what you meant by “One is > crystal, the other is cartesian”? > Let me restate my situation for clarity. > > In my band-structure input (pw.scf.bands.in, calculation = 'bands') for > a 2-D material with ibrav = 8, I specify the k-path in crystal > coordinates: > > K_POINTS crystal_b > 5 > 0.00 0.00 0.00 10 !G > 0.50 0.00 0.00 10 !X > 0.50 0.50 0.00 10 !C > 0.00 0.50 0.00 10 !Y > 0.00 0.00 0.00 10 !G > > After running this SCF/bands calculation and then bands.x with > &bands > prefix = 'A' > filband = 'B.dat' > lsym = .false. > / > > the bands.x output lists: > high-symmetry point: 0.0000 0.0000 0.0000 x coordinate 0.0000 > --> G > high-symmetry point: 0.5000 0.0000 0.0000 x coordinate 0.5000 > --> X > high-symmetry point: 0.5000 1.7459 0.0000 x coordinate 2.2459 > --> Not C > high-symmetry point: 0.0000 1.7459 0.0000 x coordinate 2.7459 > --> Not Y > high-symmetry point: 0.0000 0.0000 0.0000 x coordinate 4.4918 > --> G > > I was expecting the same crystal coordinates as in the input, but > bands.x reports larger y-values such as 1.7459.(attached bands.x output) > Could you please advise me on how to get the output high-symmetry points > to match the crystal coordinates I set in the input (pw.scf.bands.in)? > > (I also notice that for simpler cells (e.g. ibrav = 1) the reported > points match the input fractions—perhaps the cell vectors) > > Thank you again for your help. > Wenusara Satheekshana > > > > ______________________________________________________________________________________________________________________________________ > On 2025-09-28 17:33, Vahid Askarpour wrote: > > One is crystal, the other is cartesian. > > > > Cheers, > > Vahid > > > > Vahid Askarpour > > Department of Physics and Atmospheric Science > > Dalhousie University > > Halifax, Canada > > > >> On Sep 28, 2025, at 8:49 AM, wenusaras <wenusa...@uom.lk> wrote: > >> > >> CAUTION: The Sender of this email is not from within Dalhousie. > >> > >> Dear QE users, > >> > >> I am new to Quantum ESPRESSO and working on a 2D material (ibrav = 8) > >> using QE v7.2. > >> For a band-structure calculation I provided the following path in the > >> pw.scf bands input: > >> > >> K_POINTS crystal_b > >> 5 > >> 0.00 0.00 0.00 10 > >> 0.50 0.00 0.00 10 > >> 0.50 0.50 0.00 10 > >> 0.00 0.50 0.00 10 > >> 0.00 0.00 0.00 10 > >> > >> The SCF run completed, and I then executed bands.x. > >> However, the bands.x output lists different high-symmetry points: > >> > >> Reading collected, re-writing distributed wavefunctions > >> high-symmetry point: 0.0000 0.0000 0.0000 x coordinate 0.0000 > >> high-symmetry point: 0.5000 0.0000 0.0000 x coordinate 0.5000 > >> high-symmetry point: 0.5000 1.7459 0.0000 x coordinate 2.2459 > >> high-symmetry point: 0.0000 1.7459 0.0000 x coordinate 2.7459 > >> high-symmetry point: 0.0000 0.0000 0.0000 x coordinate 4.4918 > >> > >> My goal is to obtain the band structure along exactly the k-path > >> specified in the input file, but the output shows different > >> coordinates > >> (e.g., 1.7459 instead of 0.5). > >> > >> Could someone clarify why bands.x is changing the path and how I can > >> ensure the high symmetry points match with the input? > >> > >> Thank You in advance > >> Wenusara Satheekshana > >> > _______________________________________________________________________________ > >> 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 users@lists.quantum-espresso.org > >> 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 users@lists.quantum-espresso.org > > https://lists.quantum-espresso.org/mailman/listinfo/users > > -- > Thank You > Wenusara > Satheekshana_______________________________________________________________________________ > 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 users@lists.quantum-espresso.org > 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 users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users
