Thallium formation rate constants

Rate constants and activation parameters have been determined for thal-lium(m)-catalysed aquation of a series of cations cw-[Co(en)2(RNHa)Cl] +, where R = H, Me, Et, Pr", or Pr The second-order rate law followed by these reactions is consistent with either of two likely mechanisms. The first is one-step attack of the thallium(m) at the co-ordinated chloride - 5 b2 attack at the thallium(m), Sud at the cobalt. The other mechanism is rapid preequilibrium formation of a chloride-bridged cobalt(m)-thallium(ni) species whose decomposition is rate-determining ... 

The photolysis of pressed pellets of thallous azide was studied by Deb and Yoffe [239]. Decomposition led to the formation of a thin surface layer which was assumed to be thallium. No induction period in the rate was observed. The rate at constant temperature for the full output of mercury lamp was proportional to the light intensity. The activation energy for decomposition was found to be 0.33 eV (405 < X < 436 nm) or 0.14 eV (320 < X < 380 nm), with a quantum yield of 2 X 10" for X = 365 nm. Studies of the photo-induced colloidal bands in TIN3 are reviewed by Wiegand (see Section D). 

Singh, S.S. and Brydon, J.E. (1969) Solubility of basic aluminium sulfates at equilibrium in solution and in the presence of montmorillonite. Soil ScL, 107, 12—16. Sipos, P., Capewell, S.G., May, P.M., Hefter, G.T, Laurenczy, G., Lukacs, F., and Roulet, R. (1997) tI-NMR and UV-Vis spectroscopic determination of the formation constants of aqueous thallium(l) hydroxo-complexes. J. Solution Chem., 26, 419-431. Srinivasan, K. and Rechnitz, G.A. (1968) Reaction rate measurements with fluoride ion-selective membrane electrode. Formation kinetics of ferrous fluoride and aluminium fluoride complexes. Anal. Chem., 40, 1818-1825. 

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