Electric and Magnetic Properties of Amalgams

Measurements of the magnetic properties based on a selection of alkali metal rich and alkali metal poor amalgams show a different behavior at higher temperatures. 

as a typical example of the first group, exhibits Pauli paramagnetism (/mol 3 x 10-5) at higher temperatures with a weak but significant temperature dependence [4], In particular the a/p phase transition for Na3Hg at 309 K is reflected in a x change of about 5%. 

Although formally a transition metal the structural chemistry of mercury as a group 12 element in amalgams shows typical features close to those of main group 13 and 14 metals. 

Extended anionic partial structures of mercury occur in some high melting amalgams (MHg2 and related examples) with medium Hg content. Significant ionic bonding contributions between M and Hg in addition to covalent Hg-Hg contributions can be assumed to be responsible for the properties of these solids. 

In mercury rich alloys such as M Hg12 (M = K, Rb), a particular situation occurs due to high coordination number (CN) polyhedra (up to CN 22) in their structures. In these compounds the electropositive atoms are located in the centers of these polyhedra and are thus spatially separated from each other. The covalent Hg-Hg interaction, as discussed above, is of minor importance in these amalgams. 

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