The URL for API requests is: https://www.exomol.com/lidb/api/

Requests are made using the GET protocol and require certain keywords to retrieve the correct LiDB data.

Firstly, requests must be made using the molecule keyword to select a specific dataset. Datasets are available for all the molecules listed on the LiDB data homepage.

The category keyword must also be provided. category=states will request total lifetimes (in seconds) for the lumped vibrational states. category=transitions will request partial lifetimes (in seconds) between the lumped vibrational states.

Data can be returned in either JSON (default) or CSV format using the format keyword. The first line returned from JSON requests contains meta-data with information on the molecule formula, isotopologue, ExoMol dataset and version, the number of states in the LiDB query, and the number of transitions in the LiDB query. The first line returned from CSV requests contains column headers of the associated dataset.

Examples of making requests through the API:

To make a request for total state lifetimes of the CaO molecule in CSV format:
https://www.exomol.com/lidb/api/?molecule=CaO&category=states&format=csv

To make a request for partial lifetimes of "transitions" between states of water (H₂O) in JSON format:
https://www.exomol.com/lidb/api/?molecule=H2O&category=transitions&format=json