Group-IIB metals

This chapter describes the formation of bonds of the group-IA and group-IIA metals to the group-IA, group-IIA, group-IB and group-IIB metals, as well as to the transition and inner transition metals. 

Equilibrium conditions for the synthesis of intermetallic phases and compounds are concisely summarized as a function of temperature and composition in the form of phase diagrams. Consequently, in the following subsections, these relationships for group-IIA-group-IIB metal systems are reviewed. The phase diagrams in ref. 1 arc used as a baseline work published before this compilation is not specifically referred to, but that reported subsequently is used, as appropriate, to modify or replace these phase diagrams. 

As a result of their reactivity, particular attention must be given to preparation and purification of the metals, the conditions under which the metals, alloys and compounds are handled and the choice of material for the containment vessel. Ultrapure group-IIB metals may be used without further purification, but it is advisable to purify the group-IIA metals by a multidistillation process, the final distillation preferably being carried out in situ. The reactants and products are best handled in an atmosphere of a purified inert gas, usually He or Ar (N2 cannot be used because of the ready formation of group-IIA metal nitrides) alternatively, they can be handled under vacuum or, in rare cases, under halide fluxes. The containment vessel is normally fabricated from a refractory. 

Anions of transition-metal carbonyls are prepared by reducing the carbonyl and react with derivatives of group-IIB metals to yield mono-, di- and even trisubstituted derivatives ... 

Electrochemical oxidation of the group-IIB metal can generate metal-metal bonds analogously to the manner described in 8.3.3.4. For example, cyclic voltammetry with Hg electrodes shows that M(CO)2dpam (M = Cr, Mo) reacts to form Hg—M bonds in two stages ... 

The interpretation and correlation of spectroscopic properties, in the context of structure and bonding, for compounds of group IB and group IIB metals, have been covered in a comprehensive review (1). It is hoped... 

The extraction of the Group IIB metals from aqueous solution is of obvious commercial importance and continues to be investigated.996-1000 The precise species which is extracted depends on the pH, but both Aliquat 336 and tri-n-butyl phosphate extract [ZnCl3]- from LiQ solution and [ZnCl4]2- from acidic media. 

Kleppa, O. J. Thermodynamic Analysis of Binary Liquid Alloys of Group IIB Metals-I. The Systems Zink—Cadmium, Zink—Gallium, Zink—Indium and Zink—Tin. Acta Met. 6, 225 (1958). 

A. T. T. Hsieh and M. J. Mays Complexes containing transition metal-Group IIB metal bonds. 

Wet Tests.— When hydrogen sulphide is passed through an acidified solution containing molybdenum, the trisulphide is thrown dowm. The precipitate dissolves in ammonium sulphide, and it is therefore in ordinary analysis separated with the Group IIb metals, namely, arsenic, antimony, tin, gold, and platinum. The last four metals may be precipitated by addition of metallic zinc, the arsenic expelled by evaporation, and, after taking to dryness with nitric acid, the molybdenum may be extracted from the residue with ammonia. The trisulphide may be reprecipitated directly by the addition of nitric acid to the solution in ammonium sulphide. A soluble sulphide added to a solution of ammonium molybdate gives a blue colour. 

The group-IIB metal dihalide is added to the solution of the transmetallating reagent either in small portions or in solution. The solubility of Hg(II) halides is not considerable, even in ether, and if solid HgXj is added, vigorous stirring is advisable. 

The group IIB metals are also capable of inserting into the metal-metal bond of a number of transition metal carbonyl complexes. The reaction procedure normally involves stirring a solution of the metal-metal-bonded complex with powdered Zn or Cd... 

Table 1. Insertion of Group IIB Metals into Transition Metal-Metal Bonds ...

Table lists the insertion products of the group IIB metals. 

The complexation of the Group IIB metals by amino-acid and related derivatives continues to be a subject of interest stability constants reported include those for histidine and its derivatives, histamine, glycylhistamine, aspartic and glutamic acids, aspargine, glutamine, glycine, cysteine, and alanine. " ... 

Mercury, a group IIB metal, is one of the most toxic pollutants among many heavy... 

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