Chemical Potential Diagram

The chemical potential diagram is the mathematical dual of the compositional phase diagram, related by a Legendre transform that swaps composition variables for their conjugate chemical potentials. Each phase becomes a convex polytope domain in chemical potential (mu) space, showing the region where that phase is thermodynamically most stable.

Binary System (Li-O) — 2D

For a binary system, the chemical potential diagram shows domain boundaries as line segments in 2D mu-space. Each line represents the stability region of a phase.

Features in this demo: interactive hover + click-to-pin tooltips, control pane for formal potentials and bounds/padding, and export options (SVG, PNG, JSON). This panel also supports the full 2D color modes (none, energy/atom, formation energy, arity, entry count) with color bar/legend where applicable.

Ternary System (Li-Co-O) — 3D

For a ternary system, stability domains are 3D polytopes. Drag to rotate the view.

Features in this demo: 3D hull rendering with domain boundaries, hover + click-to-pin tooltips, camera and display controls, color modes/scales, and export options (PNG, SVG snapshot, JSON, view JSON, GLB). Projection switching is intentionally hidden here because this is a true ternary system.

Ternary System (Li-Fe-O) — 3D

Li-Fe-O ternary from pymatgen test data. Axes: x=Li, y=Fe, z=O.

Features in this demo: same core 3D interactions as Li-Co-O, useful as a parity/reference dataset against pymatgen expectations (domain topology, labels, and energy-aware coloring).

Ternary System (Li-Fe-O) with Temperature Slider — 3D

This demo uses the same synthetic G(T) dataset recipe as the convex-hull demo page. Drag the temperature slider to recompute stability domains from free energies.

300–1500 K

Quaternary System (Li-Co-Ni-O) — All Ternary Projections

For quaternary and higher systems, a single 3D diagram projects onto 3 chosen elements, hiding assumptions about the remaining chemical potentials. Grid mode shows all C(n,3) ternary projections simultaneously for a complete picture.

YTOS Quaternary — Ti-S-Y Projection

Full Y-Ti-O-S quaternary projected onto Ti-S-Y axes with Y2Ti2S2O5 overlay.

Features in this demo: multinary projection mode (4D system projected into 3D), runtime projection axis switching in the 3D controls pane (X/Y/Z selectors + presets), and formula overlay tooling (searchable picker, surface/neighbor quick-select actions).

YTOS — Ti-Y-O with Y2Ti2O7

Same quaternary data projected onto Ti-Y-O axes.

Features in this demo: alternative projection of the same multinary dataset, showing how domain geometry and visible phase relationships change with axis selection while preserving the same underlying computed chemical-potential domains.