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Materials Cloud MC3D in Duaer

In Duaer: Relaxed 3D crystal structures computed with PBE in Materials Cloud MC3D, by formula or elements, with cell volume, energy, and source database. One successful search uses 1 credit.

What you get

Duaer Materials Cloud MC3D searches the MC3D database of experimentally known 3D crystals relaxed with DFT (PBE) by the Materials Cloud team. Each row names the experimental database the structure came from.

Pick Duaer Data → Materials Cloud MC3D in the node creator, or open the data market. Related: Materials Project, Alexandria.

When to use it

  • Get a DFT-relaxed version of a known experimental crystal.
  • Compare cell volume and magnetization across polymorphs.

When not to use it

Search on the canvas

  1. Open the node creator and pick Duaer Data → Materials Cloud MC3D.
  2. Fill Formula (such as SiO2) or Elements (such as Si,O).
  3. Limit defaults to 10, max 20. Execute.

A search uses 1 credit only when it returns rows. No rows, wrong input, or an upstream failure uses 0.

Call the API

  • GET https://api.duaer.com/v1/data/materials-cloud?formula=SiO2
  • Authorization: Bearer <Duaer key>

The call skill below matches Copy skill in the Duaer data market, with parameters, examples, and result fields.

Call skill

Same text as Copy skill.

---
name: duaer-materials-cloud
description: >-
  Duaer Materials Cloud MC3D. Relaxed 3D crystal structures computed with PBE in Materials Cloud MC3D, by formula or elements, with cell volume, energy, and source database.
  One successful search uses 1 Duaer credit.
---

# Duaer Materials Cloud MC3D

Duaer Materials Cloud MC3D searches the MC3D database of experimentally known 3D crystals relaxed with DFT (PBE) by the Materials Cloud team. Each row names the experimental database the structure came from.

## When to use

- Get a DFT-relaxed version of a known experimental crystal.
- Compare cell volume and magnetization across polymorphs.

## When not to use

- Band gaps and hull stability. Use https://skills.duaer.com/materials-project.md.
- Raw experimental CIFs. Use https://skills.duaer.com/cod.md.

## Call

`GET https://api.duaer.com/v1/data/materials-cloud?formula=SiO2`

Header: `Authorization: Bearer <Duaer key>`

Use an account key or a model API key.

Get a Duaer key: https://skills.duaer.com/keys.md

## Parameters

Provide `formula` or `elements`.

- `formula` — Formula such as SiO2. Matches the reduced formula.
- `elements` — Optional. Materials that contain all of these, such as Si,O.
- `limit` — Optional. Rows to return, from 1 to 20. Default 10.

## Examples

- `GET https://api.duaer.com/v1/data/materials-cloud?formula=SiO2` — relaxed silica polymorphs.
- `GET https://api.duaer.com/v1/data/materials-cloud?elements=Li,Co,O&limit=5` — lithium cobalt oxides.

## Result

The response is `{ "items": [...] }`. Each item has `source`, `title`, `url`, and `summary`, plus:

- `structureId` — provider id.
- `formula`, `formulaCell`, `elements`, `sites` — reduced formula, cell formula, elements, and atoms in the cell.
- `mc3dId`, `sourceDatabase`, `sourceId` — MC3D id and the experimental source (such as mpds or cod).
- `totalEnergyEv`, `cellVolumeA3`, `totalMagnetization` — DFT energy, cell volume in ų, and magnetization.

Fields without a value are left out.

## Credits

A search that returns at least one row uses 1 credit.
An empty search, a search that finds nothing, or a failed search uses 0.
Wrong input returns 400 with a message and uses 0.
No remaining credits returns 402 and does not search.
A missing key returns 401.

## Related

- https://skills.duaer.com/materials-project.md — Duaer Materials Project
- https://skills.duaer.com/alexandria.md — Duaer Alexandria

Questions

How many credits does a Materials Cloud MC3D search use in Duaer?

One credit when Duaer returns rows. A search with no rows or an error uses 0.

Where do Duaer Materials Cloud MC3D structures come from?

Duaer Materials Cloud MC3D holds experimentally known 3D crystals relaxed with DFT (PBE). Each row names the source experimental database.

In this section

Get started

Materials Project in Duaer

In Duaer: Computed inorganic materials from the Materials Project by formula or by elements they contain, with material id, formula, elements, and site count. One successful search uses 1 credit.

Get started

Alexandria in Duaer

In Duaer: Millions of DFT structures in the Alexandria PBE database by formula or elements: band gap, formation energy, and distance to the hull. One successful search uses 1 credit.