You provide an operation plus its inputs — search filters, a query pattern, or a pattern ID. The operation choice is what most shapes the result, since it determines which filters and data each request needs.

OpXRD inputs and parameters

Operation selection

The operation parameter determines which OpXRD function to execute:

Operation	Description	Required Inputs
`search_patterns`	Filter database by element, formula, or space group	At least one filter
`similarity_search`	Find similar patterns using CrystalNN fingerprints	`two_theta_values` + `intensities`
`compute_fingerprint`	Generate a fingerprint from a crystal structure	`cif_content` or `structure_dict`
`get_pattern`	Retrieve a specific pattern by ID	Pattern ID
`list_institutions`	Browse contributing institutions	None
`compute_statistics`	Get aggregate database statistics	None

search_patterns parameters

Parameter	Type	Required	Default	Description
`elements`	string[]	No	`[]`	Filter by element symbols (e.g., `["Fe", "O"]`). Auto-extracted from `chemical_formula` if omitted.
`elements_exclusive`	boolean	No	`false`	If `true`, a pattern must contain ONLY the listed elements (exact composition, not a superset)
`spacegroup`	integer	No	`null`	Filter by spacegroup number (1-230) — not a Hermann-Mauguin symbol
`spacegroup_range`	[integer, integer]	No	`null`	Filter by an inclusive spacegroup-number range `[min, max]`
`chemical_formula`	string	No	`null`	Chemical formula (e.g., `"Fe2O3"`)
`min_atoms` / `max_atoms`	integer	No	`null`	Filter by unit-cell atom count
`volume_min` / `volume_max`	number	No	`null`	Filter by unit cell volume (Å³)
`label_type`	string	No	`null`	`fully_labeled`, `lattice_labeled`, `partially_labeled`, `unlabeled`, or `any`
`institution`	string	No	`null`	Filter by contributing institution
`max_results`	integer	No	`100`	Maximum patterns to return

Element filter examples

Filter	elements_exclusive	Matches
`["Fe", "O"]`, `false`	Iron oxides, iron oxyhydroxides, etc.
`["Fe", "O"]`, `true`	Only pure iron-oxygen compounds
`["Ti"]`, `false`	Any titanium-containing compound

similarity_search parameters

Parameter	Type	Required	Default	Description
`two_theta_values`	number[]	Yes	--	2-theta values (degrees) of the query pattern
`intensities`	number[]	Yes	--	Intensity values of the query pattern, same length and order as `two_theta_values`
`similarity_threshold`	number	No	`0.8`	Minimum similarity score (0.0-1.0)
`similarity_metric`	string	No	`"cosine"`	`cosine`, `pearson`, or `euclidean`
`max_results`	integer	No	`100`	Maximum similar patterns to return

There is no separate pattern_data/wavelength field for this operation — provide the two arrays directly:

{
  "operation": "similarity_search",
  "two_theta_values": [10.0, 20.5, 25.3, 30.1],
  "intensities": [100, 350, 800, 450]
}

compute_fingerprint parameters

Parameter	Type	Required	Description
`cif_content`	string	One of the two	CIF file content for the structure to fingerprint
`structure_dict`	object	One of the two	Pymatgen structure dict, as an alternative to `cif_content`

This operation takes a crystal structure, not a raw diffraction pattern — it is not the same input shape as similarity_search. The platform's tool schema does not currently expose a cif_content/structure_dict field for OpXRD, so this operation may not be reachable from chat; see PyWPEM if you need a fingerprint or comparison derived directly from a raw pattern.

get_pattern parameters

Parameter	Type	Required	Description
`pattern_id`	string	Yes	OpXRD database pattern identifier

Shared output options

Parameter	Type	Default	Description
`offset`	integer	`0`	Pagination offset
`include_pattern_data`	boolean	`true`	Include full 2-theta/intensity data in results
`include_structure`	boolean	`true`	Include crystal structure details in results
`include_fingerprint`	boolean	`false`	Compute and include CrystalNN fingerprints (slower)

Input validation rules

Elements: Must be valid element symbols from the periodic table
Spacegroup: A numeric spacegroup (1-230), not a Hermann-Mauguin symbol — use chemical_formula or elements if you only know the symbol
Similarity search: two_theta_values and intensities must both be present, with matching lengths
Similarity threshold: Must be between 0.0 and 1.0. Values below 0.5 may return many low-quality matches
At least one criterion: search_patterns needs at least one of elements, chemical_formula, pattern_id, spacegroup/spacegroup_range, or a similarity-search pair — otherwise the tool returns an error rather than the whole database

OpXRD inputs and parameters