Hexachloroplatinate dianion

Fig. 6 (a) 2-D 7) maps, (b) their 1-D central cross sections, and (c) the 1-D profiles of hexachloroplatinate dianion distributions obtained by electron probe analyzer measurements. S-2 and S-3 identify different porous alumina pellets, both prepared with an egg-shell distribution of hexachloroplatinate dianion the dianion is located towards the external surface of the pellet). S-2 and S-3 differ in terms of their nominal diameter and their pore-size and surface-area characteristics. Reprinted with permission from ref. 24. Copyright (2000) American Chemical Society. 

The so-called platinum carbonyl readily reacts further with alkali, dissolving to give a series of dianions with general formula [Pt3(CO)6]n2- (n = 6, 5, 4, 3, 2). Each of these dianions can be obtained in a pure state by careful control of the initial OH /Pt(IV) ratio (n = 3, OH-/Pt = 8-9 n = 4, OH-/Pt = 6-6.1 n = 5, OH /Pt = 5.7). However, these ratios are quite critical and the reaction must be followed by IR. If the incorrect product is formed, the desired final product can be obtained by adding further small amounts of alkali or of sodium hexachloroplatinate. 

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