Diborane(4)

Diborane is a transient inorganic compound with the chemical formula. Stable derivatives are known.
Diborane has been produced by abstraction of two hydrogen atoms from diborane(6) using atomic fluorine and detected by photoionization mass spectrometry. Computational studies predict a structure in which are two hydrogen atoms bridging the two boron atoms via three-centre two-electron bonds in addition to the 2-centre, 2-electron bond between the two boron atoms and one terminal hydrogen atom bonded to each boron atom.
Several stable derivatives of diborane have been reported.