How to visualize Fermi-surface in CINEMAS

CINEMAS can visualize Fermi-surface in its component CINEMAS-view.

Fermi-surface calculation can be performed using CINEMAS, and then CINEMAS-view can display 3D Fermi-surface automatically from VASP output files.

Alternatively, a folder containing VASP files of a Fermi-surface calculation can be imported to CINEMAS, and then 3D Fermi-surface can be visualized in CINEMAS-view.

Examples of Nonmagnetic Al

  • Fig. 159 shows a workflow loaded in CINEMAS. This calculation could be performed within CINEMAS, or imported to CINEMAS.


Fig. 159 Workflow displaying a Fermi-surface calculation for Al-Nonmagnetic in CASCADE.

  • Once can switch to CINEMAS-view by clicking the icon on the workflow or directly as highlighted in Fig. 160


Fig. 160 Switch to CINEMAS-view to view Fermi-surface there.

  • Left pan on CINEMAS-view, shows a tree of workflows and list of files supported by CINEMAS-view therein.

  • Visualization need not to be set for POSCAR necessarily for Fermi-surface visualization.

  • Any file(POSCAR/CONTCAR/PARCHG/LOCPOT/ELFCAR/CHGCAR) can be visualized from the workflow, Al-Nonmagnetic in this example(See Fig. 161).


Fig. 161 CINEMAS-view displaying the structure from the workflow Al-Nonmagnetic from CASCADE.

  • Fermi-surface workspace can be invoked by the button FS as highlighted in the Fig. 161 or Fig. 162.


Fig. 162 Invoking Fermi-surface workspace from the CINEMAS-view toolbar.

  • Invoking Fermi-surface workspace, prompts a window as shown in Fig. 162. This displays a few informations about the system, in this example Al-Nonmagnetic:

    • No. of band.

    • The value of Fermi-energy.

    • Type of system: Magnetic or Non-Magnetic.

    • Bands crossing or NOT crossing Fermi-level, along with respective band indices

  • Fig. 163 shows how different options can be selected to visualize Fermi-surface.

    • Fig. 163-(a): All the bands crossing Fermi-level can be selected for visualization.

    • Fig. 163-(b): Selective bands crossing Fermi-level can be selected for visualization.

    • Fig. 163-(c): Selective bands crossing or not crossing Fermi-level can be selected together for visualization.


Fig. 163 Different ways to select bands to visualize Fermi-surface for.

  • For this example, options as shown in Fig. 163-(a) are selected.

  • By clicking the OK button, CINEMAS-view switches to Fermi-surface visualization, as shown in the Fig. 164.

  • Since, options as shown in the Fig. 163-(a) were selected with two bands #2 and #3 crossing the Fermi-level.

  • First tab displays 3D Fermi-surface for band #2.

  • Second tab displays 3D Fermi-surface for band #3.

  • Third tab displays a merged view of band #2 and #3 together(see Fig. 164).


Fig. 164 Fermi-surface for individual band #2.

  • On the right side, from Style Options, view-mode can be changed, or different style-settings can be applied.

  • For individual bands, default mode of visualization is Surface in reciprocal unitcell (Fig. 164).

  • Mode can be changed to Surface in BZ (Fig. 165). BZ stands for Brillouin Zone.


Fig. 165 Fermi-surface for individual band #2, in surface in BZ mode.

  • Another mode is Repeated surface in BZ (Fig. 166).


Fig. 166 Fermi-surface for individual band #2, in Repeated surface in BZ mode.

  • Fig. 167 displays Fermi-surface for band #3, and modes or style-settings can be changed from Style Options.


Fig. 167 Fermi-surface for individual band #3.

  • Fig. 168 displays merged view of Fermi-surfaces for band #2, and #3.

  • Multiple, Line/Color properties can be changed/applied from the Style Options as shown on the right side of the Fermi-surface visualizer.


Fig. 168 Merged view of Fermi-surfaces for band #2, and #3.

  • For example, for band #2, and #3 Fermi surface can be shown as wired type instead of solid type of surface(see Fig. 169 and Fig. 170).

  • Importantly, from Style Options, Interpolate slider can be used to interpolate Fermi-surface data points, to make surface look smoother.

  • CINEMAS supports interplolation upto 6X.


Fig. 169 Displaying Fermi-surface of wired-surface type, for individual band #2.


Fig. 170 Displaying Fermi-surface of wired-surface type, for individual band #3.

  • Finally, by a single click on the button send2draw, graphics from the Fermi-surface visualizer can be exported to CINEMAS-draw to create a figure of publication-standard.

  • Graphics from the screen as shown in the Fig. 168 is exported to CINEMAS-draw as shown in the Fig. 171.

  • Text-box and the effects are added additionally.


Fig. 171 One-click export of graphics from Fermi-surface viewer to CINEMAS-draw to futher prepare figure of publication-standards. Text box is added separately.

  • Fermi-surface visualized within CINEMAS for 1) Nonmagnetic Aluminium Fig. 104, 2) Nonmagnetic Copper Fig. 105, and 3) Nonmagnetic Titanium Fig. 106.