---
title: "Get SubstratesDoc documents"
method: GET
path: "/materials/substrates/"
tags: ["Materials Substrates"]
---

# Get SubstratesDoc documents

`GET /materials/substrates/`

## Query parameters

- `film_orientation` string, nullable — Comma separated integers defining the film surface orientation.
- `substrate_orientation` string, nullable — Comma separated integers defining the substrate surface orientation.
- `area_max` number, nullable — Query for maximum value of area
- `area_min` number, nullable — Query for minimum value of area
- `energy_max` number, nullable — Query for maximum value of energy
- `energy_min` number, nullable — Query for minimum value of energy
- `norients_max` integer, nullable — Query for maximum value of norients
- `norients_min` integer, nullable — Query for minimum value of norients
- `norients` integer, nullable — Query for norients being equal to an exact value
- `norients_not_eq` integer, nullable — Query for norients being not equal to an exact value
- `norients_eq_any` string — Query for norients being any of these values. Provide a comma separated list.
- `norients_neq_any` string — Query for norients being not any of these values. Provide a comma separated list.
- `sub_form` string, nullable — Query for sub_form being equal to a value
- `sub_form_not_eq` string, nullable — Query for sub_form being not equal to a value
- `sub_form_eq_any` string — Query for sub_form being any of these values. Provide a comma separated list.
- `sub_form_neq_any` string — Query for sub_form being not any of these values. Provide a comma separated list
- `sub_id` string, nullable — Query for sub_id being equal to a value
- `sub_id_not_eq` string, nullable — Query for sub_id being not equal to a value
- `sub_id_eq_any` string — Query for sub_id being any of these values. Provide a comma separated list.
- `sub_id_neq_any` string — Query for sub_id being not any of these values. Provide a comma separated list
- `film_id` string, nullable — Query for film_id being equal to a value
- `film_id_not_eq` string, nullable — Query for film_id being not equal to a value
- `film_id_eq_any` string — Query for film_id being any of these values. Provide a comma separated list.
- `film_id_neq_any` string — Query for film_id being not any of these values. Provide a comma separated list
- `_page` integer — Page number to request (takes precedent over _limit and _skip).
- `_per_page` integer — Number of entries to show per page (takes precedent over _limit and _skip). Limited to 1000.
- `_skip` integer — Number of entries to skip in the search.
- `_limit` integer — Max number of entries to return in a single query. Limited to 1000.
- `_fields` string — Fields to project from SubstratesDoc as a list of comma separated strings. Fields include: `sub_form` `sub_id` `film_orient` `area` `energy` `film_id` `norients` `orient`
- `_all_fields` boolean — Include all fields.

## Response `200`

Search for a SubstratesDoc

- ResponseSubstratesDoc
  - `data` SubstratesDoc[], nullable — List of returned data
    - `sub_form` string, nullable — Reduced formula of the substrate.
    - `sub_id` string, nullable — Materials Project ID of the substrate material. This comes in the form: mp-******.
    - `film_orient` string, nullable — Surface orientation of the film material.
    - `area` number, nullable — Minimum coincident interface area in Ų.
    - `energy` number, nullable — Elastic energy in meV.
    - `film_id` string, nullable — The Materials Project ID of the film material. This comes in the form: mp-******.
    - `_norients` integer, nullable — Number of possible surface orientations for the substrate.
    - `orient` string, nullable — Surface orientation of the substrate material.
  - `errors` Error[], nullable — Any errors on processing this query
    - `code` integer, required — The error code
    - `message` string, required — The description of the error
  - `meta` Meta — Meta information for the MAPI Response.
    - `api_version` string — A string containing the version of the Materials API implementation, e.g. v0.9.5
    - `time_stamp` string, date-time — A string containing the date and time at which the query was executed
    - `total_doc` integer, nullable — The total number of documents available for this query
    - `facet` object, nullable — A dictionary containing the facets available for this query

## Other responses

- `422` — Validation Error

## Changes

- **2026-08-20** `70f72d0670df` — 1 info
  - the `api_version` response's property default value changed from `0.87.2.dev19+g3f2daf4f8` to `0.87.3.dev3+gfbe8656b6` for the status `200`
- **2026-07-31** `54f2f79ab4f8` — 1 info
  - the `api_version` response's property default value changed from `0.87.2.dev13+g62063a867` to `0.87.2.dev19+g3f2daf4f8` for the status `200`
- **2026-07-26** `9aac4fdf4081` — 1 info
  - the `api_version` response's property default value changed from `0.87.2.dev4+g6bd8ed856` to `0.87.2.dev13+g62063a867` for the status `200`

[Change history](https://skmtc.dev/materialsproject/apis/materials-project-api/changes/materials/substrates/get.md)

---

[API](https://skmtc.dev/materialsproject/apis/materials-project-api.md) · [All operations](https://skmtc.dev/materialsproject/apis/materials-project-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/materialsproject/materials-project-api/revisions/70f72d0670df/schema)