https://doi.org/10.1351/goldbook.B00703
The bonding number \(n\) of a @S05706@ is the sum of the total number of bonding equivalents (@V06588@ bonds) of that @S05706@ to adjacent skeletal atoms in a @P04405@, if any, and the number of attached hydrogen atoms, if any. Examples: SH2: for S, \(n=2\); SH6: for S, \(n=6\).