Cobalticyanides

A TRIRETICULATE CRYSTAL STRUCTURE TRIHYDROGEN COBALTICYANIDE AND TRISILVER COBALTICYANIDE ... 

We have found that the observed X-ray intensities for trisilver cobalticyanide are incompatible with the structure suggested by Ludi et al., and correspond instead to a structure in which each cobalticyanide group is connected through covalently bonded silver atoms to cobalticyanide groups that are related to it by translation by the amount a + c, rather than by c. 

Fig. 1.—A simple cubic framework of trisilver cobalticyanide. The circles, in increasing size, represent silver, cobalt, carbon, and nitrogen, respectively.

Fig. 2.—Representation of three mutually interpenetrating cubic frameworks of trisilver cobalticyanide, each displaced to another by translation by one third along the body diagonal of the unit cube.

Fig. 3.—The structure of trisilver cobalticyanide. There are three mutually interpenetrating rhombohedral frameworks, distorted from the cubic frameworks of Fig. 2 in such a way as to achieve increased density and closer approximation to the optimal packing of the bulky cobalticyanide groups.

Summary.—The crystals trisilver cobalticyanide and trihydrogen cobalticyanide have been shown to have a trireticulate structure, with nearly regular cobalticyanide octahedra connected by nitrogen-silver-nitrogen bonds or by hydrogen bonds between the nitrogen atoms. 

Potassium cobalticyanide [13963-58-1 ] M 332.4. Crystd from water to remove traces of HCN. 

The formation of the cobalticyanide may be traced as alloy with three per cent, of nickel is perfectly malle- ... 

Propagation of error. A mixture containing only silver nitrate and mercurous nitrate was dissolved in water and treated with excess sodium cobalticyanide, Na3[Co(CN)6] to precipitate both cobalticyanide salts ... 

According to some authorities, the first metal ammine to be isolated in the solid state was the reddish yellow hexaamminecobalt(III) oxalate [Co(NH3)6]2(C204)3, described in 1822 by Leopold Gmelin (1788-1853).16 Gmelin also discovered several new double salts potassium ferricyanide, or potassium hexacyanoferrate(III), K3[Fe(CN)6l>17 the cobalticyanides or hexacyanocobaltates(III), M3[Co(CN) ],18 and the platinocyanides or tetracyanoplatinates(II), M2[Pt(CN)4].19All these substances certainly deserve to rank among the earliest known coordination compounds. 

Chromicyanides, manganicyanides, cobalticyanides, ruthenocyanides, and osmocyanides, are also known, similar in formulas to the ferro- and ferri-cyanides. On the other hand, nickel and platinum form double cyanides similar in formula to K2Pt(CN)4. The platinum salts are very beautiful, possessing the property of dichroism, i.e. of transmitting light different in colour from that which the crystals reflect moreover, only some of the facets of the crystals have this property. 

Boclair, J. W., Braterman, R S., Brister, B. D. and Yarberry, F. (1999). Layer-anion interactions in magnesium aluminum layered double hydroxides intercalated with cobalticyanide and nitroprusside. Chem. Mater. 11, 2199. 

Place a few drops of the neutral (litmus) test solution upon potassium hexa-cyanocobaltate(III) (or cobalticyanide, Rinmann s green) test paper. Dry the paper over a flame and ignite in a small crucible. Observe the colour of the ash against a white background part of it will be green. 

The potassium hexacyanocobaltate(III) (or cobalticyanide) test paper is prepared by soaking drop-reaction paper or quantitative filter paper in a solution containing 4 g potassium hexacyanocobaltate(III) and 1 g potassium chlorate in 100 ml water, and drying at room temperature or at 100°C. The paper is yellow and keeps well. 

Potassium hexacyanocobaltate(HI) reagent (4%). Dissolve 4g potassium hexacyanocobaltate(III) (potassium cobalticyanide) K3[Co(CN)6] and 1 g potassium chlorate, KC103, in water and dilute to 100 ml. 

This compound chelates cyanide as cobalticyanide. This drug is known to antagonize cyanide more quickly than the nitrites but its clear superiority has not been established. Intravenous administration of 300 mg of dicobalt edetate in glucose solution is the current treatment of choice in France and the United Kingdom. Serious side effects like vomiting, urticaria, anaphylactoid shock, hypotension, and ventricular arrythmias have been reported in patients receiving Kelocyanor (Van Heijst and Meredith, 1990). 

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