| Diborane | |
|---|---|
| Diborane | |
| General | |
| Molecular formula | B2H6 |
| Molar mass | 27.67 g/mol |
| Appearance | colorless gas |
| CAS number | [19287-45-7] |
| Properties | |
| Density and phase | 1.18 g/l, gas (15 °C) |
| Solubility in water | Reacts |
| Melting point | −165 °C (108 K) |
| Boiling point | −92.5 °C |
| Structure | |
| Molecular shape | see text |
| Coordination geometry |
Tetrahedral (for boron) |
| Dipole moment | 0 D |
| Hazards | |
| MSDS | External MSDS |
| EU classification | not listed |
| NFPA 704 | Template:Nfpa |
| Flash point | flammable gas |
| Autoignition temperature | 38 °C |
| Explosive limits | 0.8–88% |
| RTECS number | HQ9275000 |
| Supplementary data page | |
| Structure and properties |
n, εr, etc. |
| Thermodynamic data |
Phase behaviour Solid, liquid, gas |
| Spectral data | UV, IR, NMR, MS |
| Related compounds | |
| Other cations | Alumane Gallane |
| Related boranes | Decaborane |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references | |
Diborane is a colorless gas at room temperature with a repulsive, sweet odor. It mixes well with air and easily forms explosive mixtures. Diborane will ignite spontaneously in moist air at room temperature. The chemical formula for this borane is B2H6. Synonyms include Boroethane, boron hydride and diboron hexahydride.
Diborane is used in rocket propellants, as a reducing agent, as a rubber vulcanizer, as a catalyst for hydrocarbon polymerization, as a flame-speed accelerator, and as a doping agent in semiconductors.
The bonding between the two bridging hydrides of diborane is unusual, being an example of 3-center-2-electron bonding.
Reactions
Health effects
The toxic effects of diborane are primarily due to its irritant properties. Short-term exposure to diborane can cause a sensation of tightness of the chest, shortness of breath, cough, and wheezing. These signs and symptoms can occur immediately or be delayed for up to 24 hours. Skin and eye irritation can also occur. Studies in animals have shown that diborane causes the same type of effects observed in humans.
People exposed for a long time to low amounts of diborane have experienced respiratory irritation, seizures, fatigue, drowsiness, confusion, and occasional transient tremors.