ChemSpider is a free chemical structure database providing fast text and structure search access to over 32 million structures from hundreds of data sources.

ICSD is the world’s largest database for fully identified inorganic crystal structures. It currently contains about 193,000 peer-reviewed data entries including their atomic coordinates. Updates are made twice a year (in spring and in fall) with data taken from scientific journals and other sources. Thanks to these many heterogeneous data sources the database has a wide coverage. ICSD is also updated retroactively. The oldest records date back to the year 1913 and contain information from publications by William Henry Bragg and his son.