Low valent magnesium compounds
Encyclopedia
Two low valent magnesium compounds have been discovered that are the first examples of stable magnesium(I) compounds. Both examples have the formula L2Mg2, where L represents a bulky anionic ligand. X-ray crystallographic studies show an Mg-Mg bond length of 285.1 pm and 284.6 pm. Theoretical studies indicate an essentially ionic formulation Mg22+(L−)2. The Mg22+ ion is the group 2
analogue of the group 12
Hg22+ (present in e.g. mercury(I) chloride
) and Cd22+ ions (present in cadmium(I) tetrachloroaluminate
). The preparation involved the reduction of MgII iodine complexes with potassium metal and the bulky ligands were:
The chemistry of Mg is dominated by the +2 oxidation state and up to this point the ternary metal hydrides Mg2RuH4, Mg3RuH3, and Mg4IrH5 and magnesium diboride
, MgB2 with short Mg-Mg bonds (293 pm, 303 pm, 275 pm, 308pm respectively)
had been assumed to contain an Mg2 unit. Calculations had also indicated the stability of the Mg22+ cation
Alkaline earth metal
The alkaline earth metals are a group in the periodic table. In the modern IUPAC nomenclature, the alkaline earth metals are called the group 2 elements. Previously, they were called the Group IIA elements . The alkaline earth metals contain beryllium , magnesium , calcium , strontium , barium and...
analogue of the group 12
Group 12 element
A group 12 element is one of the elements in group 12 in the periodic table. This includes zinc , cadmium and mercury . The further inclusion of copernicium in group 12 is supported by recent experiments on individual Cn atoms...
Hg22+ (present in e.g. mercury(I) chloride
Mercury(I) chloride
Mercury chloride is the chemical compound with the formula Hg2Cl2. Also known as calomel or mercurous chloride, this dense white or yellowish-white, odorless solid is the principal example of a mercury compound...
) and Cd22+ ions (present in cadmium(I) tetrachloroaluminate
Cadmium(I) tetrachloroaluminate
Cadmium tetrachloroaluminate is the inorganic compound with the formula Cd22, a tetrachloroaluminate of cadmium. It was the first compound reported that contained cadmium in the +1 oxidation state...
). The preparation involved the reduction of MgII iodine complexes with potassium metal and the bulky ligands were:
- a guanidinate, "priso", [(Ar)NC(NPri2)N(Ar)]– where Ar = 2,6-diisopropylphenyl and Pri = iso-propyl
- a ketiminate, "nacnac", {[(Ar)NC(Me)]2CH}−,- where Ar = 2,6-diisopropylphenyl and Me = methyl
The chemistry of Mg is dominated by the +2 oxidation state and up to this point the ternary metal hydrides Mg2RuH4, Mg3RuH3, and Mg4IrH5 and magnesium diboride
Magnesium diboride
Magnesium diboride is a simple ionic binary compound that has proven to be an inexpensive and useful superconducting material.Its superconductivity was announced in the journal Nature in March 2001. Its critical temperature of is the highest amongst conventional superconductors...
, MgB2 with short Mg-Mg bonds (293 pm, 303 pm, 275 pm, 308pm respectively)
had been assumed to contain an Mg2 unit. Calculations had also indicated the stability of the Mg22+ cation