Tutorial: Plotting projected EBS & DOS with colormap scaling #

Step 1: Upload files and parse #

Upload both EBS and DOS inputs first, then click Parse. In combined mode, one workflow drives both plots and report updates together.

Review generated report cards #

After parsing, the page generates report cards that summarize key results. You can expect values such as bandgap, material type, Fermi value, lattice parameters, angles, volume, and density. If the simulation is spin-polarized and the bandgaps differ between channels, the report card shows separate Spin ↑ and Spin ↓ bandgap entries.

If you want this report in different units, use the Units panel in the right sidebar.

Step 2: Limits and navigation #

In EBS & DOS mode, the Limits panel has three sections two for x-axis and one for the shared y-axis:

EBS: X min and X max define the x-axis limits for the band-structure plot. You can set these limits using high-symmetry-point indices instead of exact k-point values. For example, for this k-path, setting X min = 0 and X max = 5 plots the range from Γ to X.

DOS: X min and X max for the density of states x-axis.

Shared: Y min and Y max for the common energy axis used by both subplots. In combined mode, the shared y-limits are driven by DOS so both panels remain aligned in energy. For this example we set the energy limits from -5 to 8 eV.

Navigation

Use the quick ribbon controls above the chart to manage interaction behavior while inspecting and presenting figures.

Step 3: Add filters and configure colormap controls #

Click Add Filter to create one projected contribution shared by both subplots. The app enables filtered EBS and filtered DOS for the first filter so the same projection definition drives both sides of the combined figure.

In the filter card, set coloring mode to Colormap, choose a colormap (for example viridis), and tune vmin/vmax to control how projection weights map to color intensity.

It is always a good idea to check your generated figure and colorbar for color blindness accessibility. You can download a PNG and upload it to a simulator such as Coblis Color Blindness Simulator.

The colormap dropdown is searchable, so you can quickly find maps by name. For examples and guidance, see the Matplotlib colormap reference: Matplotlib Colormaps. If you want the opposite gradient direction, enable the Reverse checkbox.

In the filter Coloring panel, Opacity controls transparency (0 = fully transparent, 1 = fully opaque). Plotting order (z-order) controls which filters are drawn on top when they overlap: higher values are rendered above lower values, while auto lets the app choose the order.

In the Values/Spins panel, the Normalize checkbox only rescales projected intensities for plotting; it is not quantum-mechanical normalization. The values depend on the selected projection basis and projection-sphere radii used in the simulation. With Auto enabled, vmin and vmax are set from the minimum and maximum projection values found in the selected input data. If the calculation is spin-polarized, this panel also shows Spin Up and Spin Down checkboxes, which you can use to include either channel alone or both channels in that filter.

Step 4: Example colormap projection #

In this example, oxygen p states are highlighted with a continuous colormap while EBS and DOS are shown side by side.

Below is an example of the filter table. We select the oxygen rows and the p_x, p_y, and p_z columns to build the O-p filter used in the final plot.

After the table selection is set, plot the combined figure. The EBS panel shows where O-p character appears along the bands, while the DOS panel shows the same selected contribution as a projected density trace on the shared energy axis.

Step 5: Tune legend and colorbar #

The legend label tile inside each filter card still controls per-filter legend styling, including label text, color, weight, and style. If you leave the label empty, DFT Hub can auto-generate the label from the selected projection.

The Color bar panel in the right sidebar controls global colorbar settings , including position and layout options such as loc X. and loc Y..

In the Color bar panel, Bar settings control placement and size (Loc. X, Loc. Y, orientation, length, width, and gap), while Text settings control readability (label font style, text direction, and text gap).

There are two color bar modes you can use in the figure: calculable and non-calculable. The calculable mode is useful for interactive analysis in the web app, while the non-calculable mode is often preferred for publication-ready figures. When Calculable is enabled, you can include or exclude bands projections above or below a threshold by dragging the color bar edges.

You can select different preset arrangements for color bar placement. The web app can automatically choose both the bar length and location. If you switch to a custom position, the Loc X. and Loc Y. fields become active and are prefilled from the latest automatically generated values.

Step 6: Customization and styling #

For axis, legend, font, colors, and other appearance controls, use the right sidebar and see the full settings reference in Plot Settings.

Step 7: Export the figure #

When your figure is ready, click the download button in the chart toolbar to export it. Use this to save a clean image for reports, slides, or publications.

If you download SVG, the figure and element positions remain fully editable when opened in software such as Adobe Illustrator, Inkscape, or GIMP.