|Systematic IUPAC name
3D model (JSmol)
|Molar mass||3.02204 g mol−1|
|Melting point||−259 °C (−434.2 °F; 14.1 K)|
|Boiling point||−253 °C (−423.4 °F; 20.1 K)|
|GHS Signal word||Danger|
|P210, P377, P381, P403, P410+P403|
|NFPA 704 (fire diamond)|
|571 °C (1,060 °F; 844 K)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|(what is ?)|
Hydrogen deuteride is a diatomic molecule substance or compound of two isotopes of hydrogen: the majority isotope 1H (protium) and 2H (deuterium). Its proper molecular formula is H2H, but for simplification, it is usually written as HD.
Hydrogen deuteride is a minor component of naturally occurring molecular hydrogen. It is one of the minor but noticeable components of the atmospheres of all the giant planets, with abundances from about 30 ppm to about 200 ppm. HD has also been found in supernova remnants, and other sources.
HD and H2 have very similar emission spectra, but the emission frequencies differ.
The frequency of the astronomically important J = 1-0 rotational transition of HD at 2.7 THz has been measured with tunable FIR radiation with an accuracy of 150 kHz.