elements

Elements is a command-line search of the PubChem Periodic Table.

(The following paragraph is what I plan to implement.)

This program allows you to search for data related to an element by number, symbol or name. Elements can deal with misspellings. You can also searched based on the properties (atomic mass between two values, having certain oxidation states, etc.)

Elements also supports querying the dedicated entries for the elements (on the pubchem website, you can access this by clicking on the element).

Copyright

The source code of this program is in the public domain (see COPYING.md).

The PubChem database does not explicitly state the license or copyright status of their periodic table data. However, the bundled file is nothing but a collection of physical facts published by the United States government without copyright notice, so I presume it is in the public domain.

The dedicated entries for specific elements from PubChem (I believe) are licensed for non-commercial use. Those will be in a seperate git repo.