Alkaline earth octacarbonyl complex

rdf:langString Alkaline earth octacarbonyl complex

rdf:langString Alkaline earth octacarbonyl complexes are a class of neutral compounds that have the general formula M(CO)8 where M is a heavy Group 2 element (Ca, Sr, or Ba). The metal center has a formal oxidation state of 0 and the complex has a high level of symmetry belonging to the cubic Oh point group. These complexes are isolable in a low-temperature neon matrix, but are not frequently used in applications due to their instability in air and water. The bonding within these complexes is controversial with some arguing the bonding resembles a model similar to bonding in transition metal carbonyl complexes which abide by the 18-electron rule, and others arguing the molecule more accurately contains ionic bonds between the alkaline earth metal center and the carbonyl ligands. Complexes of Be(CO)8 and Mg(CO)8 are not synthetically possible due to inaccessible (n-1)d orbitals. Beryllium has been found to form a dinuclear homoleptic carbonyl and magnesium a mononuclear heteroleptic carbonyl, both with only two carbonyl ligands instead of eight to each metal atom.