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Titanium(II) chloride
Encyclopedia
Titanium chloride is the chemical compound
with the formula
TiCl2. The black solid has been studied only moderately, probably because of its high reactivity. Ti(II) is a strong reducing agent: it has a high affinity for oxygen and reacts irreversibly with water to produce H2. The usual preparation is the thermal disproportionation
of TiCl3 at 500 °C. The equilibrium is "driven" by the loss of volatile TiCl4
:
The method is similar to that for the conversion of VCl3
into VCl2
and VCl4.
TiCl2 crystallizes as the layered CdI2
structure. Thus, the Ti(II) centers are octahedrally coordinated to six chloride ligands.
((CH3)2PCH2CH2P(CH3)2 and TMEDA ((CH3)2NCH2CH2N(CH3)2). Such species are prepared by reduction of related Ti(III) and Ti(IV) complexes.
Unusual electronic effect
s have been observed in these species: TiCl2[(CH3)2PCH2CH2P(CH3)2]2 is paramagnetic with a triplet ground state
, but Ti(CH3)2[(CH3)2PCH2CH2P(CH3)2]2 is diamagnetic.
A solid-state derivative of TiCl2 is Na2TiCI4, which has been prepared by the reaction of Ti metal with TiCl3 in a NaCl flux
. This species adopts a linear chain structure wherein again the Ti(II) centers are octahedral with terminal, axial halides.
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...
with the formula
Chemical formula
A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....
TiCl2. The black solid has been studied only moderately, probably because of its high reactivity. Ti(II) is a strong reducing agent: it has a high affinity for oxygen and reacts irreversibly with water to produce H2. The usual preparation is the thermal disproportionation
Disproportionation
Disproportionation, also known as dismutation is used to describe a specific type of redox reaction in which a species is simultaneously reduced and oxidized so as to form two different products....
of TiCl3 at 500 °C. The equilibrium is "driven" by the loss of volatile TiCl4
Titanium tetrachloride
Titanium tetrachloride is the inorganic compound with the formula TiCl4. It is an important intermediate in the production of titanium metal and the pigment titanium dioxide. TiCl4 is an unusual example of a metal halide that is highly volatile...
:
-
- 2 TiCl3 → TiCl2 + TiCl4
The method is similar to that for the conversion of VCl3
Vanadium(III) chloride
Vanadium trichloride is the inorganic compound with the formula VCl3. This purple salt is a common precursor to other vanadium complexes.-Structure:...
into VCl2
Vanadium(II) chloride
Vanadium chloride is the inorganic compound with the formula VCl2. This purple solid is the most reduced vanadium chloride. Like other metal dihalides, it is a polymer...
and VCl4.
TiCl2 crystallizes as the layered CdI2
Cadmium iodide
Cadmium iodide, CdI2, is a chemical compound of cadmium and iodine. It is notable for its crystal structure, which is typical for compounds of the form MX2 with strong polarization effects.-Uses:...
structure. Thus, the Ti(II) centers are octahedrally coordinated to six chloride ligands.
Derivatives
Molecular complexes are known such as TiCl2(chel)2, where chel is DMPE1,2-Bis(dimethylphosphino)ethane
1,2-Bisethane is a diphosphine ligand in coordination chemistry. It can be synthesised by the reaction of methylmagnesium iodide with 1,2-bisethane:...
((CH3)2PCH2CH2P(CH3)2 and TMEDA ((CH3)2NCH2CH2N(CH3)2). Such species are prepared by reduction of related Ti(III) and Ti(IV) complexes.
Unusual electronic effect
Electronic effect
An electronic effect influences the structure, reactivity, or properties of molecule but is neither a traditional bond nor a steric effect. In organic chemistry, the term stereoelectronic effect is also used to emphasize the relation between the electronic structure and the geometry of a...
s have been observed in these species: TiCl2[(CH3)2PCH2CH2P(CH3)2]2 is paramagnetic with a triplet ground state
Ground state
The ground state of a quantum mechanical system is its lowest-energy state; the energy of the ground state is known as the zero-point energy of the system. An excited state is any state with energy greater than the ground state...
, but Ti(CH3)2[(CH3)2PCH2CH2P(CH3)2]2 is diamagnetic.
A solid-state derivative of TiCl2 is Na2TiCI4, which has been prepared by the reaction of Ti metal with TiCl3 in a NaCl flux
Flux
In the various subfields of physics, there exist two common usages of the term flux, both with rigorous mathematical frameworks.* In the study of transport phenomena , flux is defined as flow per unit area, where flow is the movement of some quantity per time...
. This species adopts a linear chain structure wherein again the Ti(II) centers are octahedral with terminal, axial halides.