A single bond between adjacent atoms that is formed by less than two electrons, as in
B2H6:
The
B–H–B bonds are called 'two-electron three-centre bonds'.
Source: PAC, 1994,
66, 1077. (
Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1110 [
Terms] [
Paper]
