A search form is included in the left-hand column of every WebMolecules page. This is a great way to search 100 percent of the WebMolecules Library.
Any valid formula comprised of element symbols and numbers is acceptable.
Please do not use dashes, parentheses, or spaces. Searching for a partial formula is also supported within our Top 2000 . A list of all matching molecules will be displayed. Registry Numbers provide a fairly complete index of known molecules. There are additional numbering rules used by CAS to maintain scheme integrity, but you needn't concern yourself about them.