The approved designations (devised by Cahn, Ingold and Prelog) of @A00020@ at four-coordinate (quadriligant) and six-coordinate (sexiligant) @S05980@ centres.
Source: PAC, 1996,
68, 2193. (
Basic terminology of stereochemistry (IUPAC Recommendations 1996)) on page 2216 [
Terms] [
Paper]