Cobalt(II) hydride
Other names
Cobalt dihydride, cobaltous hydride
3D model (JSmol)
  • InChI=1S/Co.2H/q+2;2*-1
  • [H-].[H-].[Co+2]
Molar mass 60.949 g·mol−1
Appearance dark grey crystals
Density 0.533 g/cm3
Occupational safety and health (OHS/OSH):
Main hazards
highly reacts
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Cobalt(II) hydride is an inorganic compound with a chemical formula CoH2. It has dark grey crystals. It oxidizes slowly in air and reacts with water.[1][2]

Two forms of cobalt(II) hydride exist under high pressure. From 4 to 45 GPa there is a face-centred cubic form with formula CoH. This can be decompressed at low temperatures to form a metastable compound at atmospheric pressure. Over 45 GPa a cobalt(II) hydride CoH2 also crystallises in a face-centred cubic form.[3]


Cobalt(II) hydride can prepared by reacting phenylmagnesium bromide and cobalt(II) chloride in hydrogen gas:

CoCl2 + 2 C6H5MgBr + 2 H2 → CoH2 + 2 C6H6 + MgBr2 + MgCl2


  1. ^ Химическая энциклопедия. Vol. 2. М.: Советская энциклопедия. 1990. ISBN 5-85270-035-5. ((cite book)): Unknown parameter |agency= ignored (help)
  2. ^ Рипан Р., Четяну И. (1972). Неорганическая химия. Химия металлов. Vol. 2. М.: Мир.
  3. ^ Wang, Mengnan; Binns, Jack; Donnelly, Mary-Ellen; Peña-Alvarez, Miriam; Dalladay-Simpson, Philip; Howie, Ross T. (13 April 2018). "High pressure synthesis and stability of cobalt hydrides" (PDF). The Journal of Chemical Physics. 148 (14): 144310. Bibcode:2018JChPh.148n4310W. doi:10.1063/1.5026535. hdl:20.500.11820/2b963cd7-cf80-42a7-8f7e-31518de1d934. ISSN 0021-9606. PMID 29655356.