Molybdenum(III) bromide is the
inorganic compound with the formula MoBr
3. It is a black solid that is insoluble in most solvents but dissolves in donor solvents such as
pyridine
Pyridine is a basic heterocyclic organic compound with the chemical formula . It is structurally related to benzene, with one methine group replaced by a nitrogen atom. It is a highly flammable, weakly alkaline, water-miscible liquid with a ...
.
Preparation
Molybdenum(III) bromide is produced by the reaction of elemental
molybdenum and
bromine
Bromine is a chemical element with the symbol Br and atomic number 35. It is the third-lightest element in group 17 of the periodic table ( halogens) and is a volatile red-brown liquid at room temperature that evaporates readily to form a simi ...
at .
[F. Hein, S. Herzog "Molybdenum(III) Bromide" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1407.]
:
It can also be prepared from the reduction of
molybdenum(IV) bromide with molybdenum metal,
hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...
gas, or a
hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...
.
It has a structure consisting of infinite chains of face-sharing octahedra with alternatingly short and long Mo-Mo contacts. The same structure is adopted by the tribromides of ruthenium and technetium.
[Dietrich Babel: ''Die Verfeinerung der MoBr3-Struktur (Refinement of the MoBr3-Structure)'' In: '' Journal of Solid State Chemistry.'' 1972, volume 4, S. 410–416, .][Order-Disorder Transformation in RuBr3 and MoBr3: A two-Dimensional Ising Model" Merlino, S.; Labella, L.; Marchetti, F.; Toscani, S. Chemistry of Materials 2004, volume 16, p3895-p3903] In contrast, in the high temperature phase of
titanium(III) iodide, the Ti---Ti separation is invariant.
References
Bromides
Molybdenum halides
Molybdenum(III) compounds
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