Diborane(2) or diborene is a theoretical/hypothetical inorganic compound with the formula B2H2. It is predicted to have a symmetric covalently bonded structure of H–B=B–H with linear geometry. It has been suggested that the boron–boron bonding in this compound may be a pure pi bond, one that does not have any net sigma bonding associated with it. The compound will be a very strong Lewis acid as each boron has a share in only 6 valence electrons.
3D model (JSmol)
|Molar mass||23.64 g·mol−1|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Related compounds, with the general formula R:(BH)=(BH):R, known as diborenes, are stable. The two substituents, R:, supply the two additional electron pairs needed for there to be a conventional double bond between the boron atoms in these compounds.
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