Similar Materials

Find materials that are structurally or compositionally similar to a given material. This is useful for exploring alternatives, finding polymorphs, or discovering isostructural compounds.

Endpoint

GET /api/materials/{material_id}/similar

Path Parameters

Query Parameters

Similarity Methods

Composition-based (method=composition): Finds materials with similar elemental composition using the Earth Mover's Distance on composition vectors. Good for finding substitution candidates.

Structure-based (method=structure): Uses structure fingerprints (radial distribution function + angular distribution) to find materials with similar local bonding environments regardless of composition.

Properties-based (method=properties): Finds materials with similar computed properties (band gap, density, formation energy) using normalized Euclidean distance in property space.

Example Request

bash

curl "https://api.matcraft.ai/api/v1/materials/mp-149/similar?method=structure&limit=5"

Example Response

json

{
  "data": [
    {
      "material_id": "mp-32",
      "formula": "Ge",
      "similarity_score": 0.97,
      "band_gap": 0.61,
      "crystal_system": "cubic",
      "space_group": "Fd-3m"
    },
    {
      "material_id": "mp-8086",
      "formula": "Sn",
      "similarity_score": 0.89,
      "band_gap": 0.0,
      "crystal_system": "cubic",
      "space_group": "Fd-3m"
    }
  ],
  "meta": {
    "reference_id": "mp-149",
    "method": "structure",
    "took_ms": 120
  }
}

Response Fields

Use Cases

Polymorph search: Find different crystal structures of the same composition
Isostructural compounds: Find materials with the same structure but different elements
Property-matched alternatives: Find cheaper or more abundant materials with similar properties