Abstract
The absorption spectra of Co(II) chloride complexes, containing variable concentrations of chloride ligand, in a molten mixture of 80 mol% acetamide–20 mol% calcium nitrate tetrahydrate, were studied at 313, 333, 353, and 363 K, in the wavelength range 400-800 nm. The melt contains three possible ligands (CH3CONH2, H2O, and NO3 -) for competition with added chloride ligand. Addition of chloride caused a shift of the absorption maximum of octahedral cobalt(II) nitrate towards lower energies and pronounced changes in the shape of the initial spectrum of cobalt(II) nitrate. The effect of temperature changes on the molar absorption coefficient of the Co(II) species was dependent on the chloride concentration and was attributed to the structural changes occurring in the cobalt(II) species. The STAR and STAR FA programs were applied to identify the complex ionic species and to calculate the stability constants of Co(II) complexes formed in this solvent. The results indicate the highest probability of formation of the following complex species: Co(NO3)4 2-, Co(NO3)2Cl2 2-, and CoCl4 2-. Stability constants of each complex were presented for the equilibria occurring at 313, 333, 353, and 363 K. Distribution of the Co(II) species was also calculated over the ranges of chloride concentration and temperature investigated.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
REFERENCES
J. Bjerrum, A. S. Halonin, and L. H. Skibsted, J. Phys. Chem. 79, 2192 (1975).
L. I. Katzin and E. Gebert, J. Am. Chem. Soc. 72, 5464 (1950).
D. M. Gruen, S. Fried, P. Graf, and R. I. McBeth, Proc. 2nd. U.N. Int. Conf. Peaceful Uses Atomic Energy, Vol. 28 (1958), p. 112.
D. H. Kerridge, R. Nikoli, and D. Stoji, J. Chem. Soc. Dalton Trans. 1663 (1986).
J. R. Dickinson, T. R. Griffiths, and P. J. Potts, J. Inorg. Nucl. Chem. 37, 511 (1975).
F. J. C. Rossotti and H. Rossotti, The Determination of Stability Constants (McGraw-Hill, New York, 1961).
D. J. Legget, S. L. Kelly, L. R. Shiue, Y. T. Wu, D. Chang, and K. M. Kadish, Talanta 30, 579 (1983).
L. G. Sillen, Acta Chem. Scand. 16, 159 (1962).
S. Hemmingsson and B. Holmberg, Inorg. Chem. 19(8), 2242 (1980).
J. Savovi, R. Nikoli, and D. H. Kerridge, Fluid Phase Equilib. 118, 143 (1996).
J. Tripkovi, (Savovi), R. Nikoli, and D. H. Kerridge, J. Serb. Chem. Soc. 54, 527 (1989).
D. H. Kerridge, Chem. Soc. Rev. 17, 181 (1988).
C. A. Angell, J. Electrochim. Acta 112, 1224 (1965).
J. H. R. Clarke, P. J. Hartley, and Y. Kuroda, Inorg. Chem. 11, 29 (1972).
V. S. Ellis and R. E. Hester, J. Chem. Soc. (A) 607 (1969).
J. L. Beltran, R. Codony, and M. D. Prat, Anal. Chim. Acta 276, 441 (1993).
D. H. Kerridge and S. A. Tariq, Aust. J. Chem. 46, 917 (1993).
D. K. Straub, R. S. Drago, and J. T. Donoghue, Inorg. Chem. 1, 848 (1962).
M. Meloun, J. Havel, and E. Hogfeldt, Computation of Solution Equilibria (Ellis Horwood, Chichester, UK, 1988).
A. Sabatini, A. Vacca, and P. Gans, Talanta 21, 53 (1974).
A. Sabatini, A. Vacca, and P. Gans, J. Chem. Soc. Dalton Trans. 115 (1978).
A. Chiboub-Fellah, J. Meullemeestre, C. Spies, F. Vierling, and M. A. Khan, Transition Metal Chem. 24, 135 (1999).
E. R. Malinowski and D. G. Howery, Factor Analysis in Chemistry (Wiley, New York, 1980).
G. P. Smith, in Molten Salt Chemistry, M. Blander, ed. (Interscience, London, 1964).
H. A. Øye and D. M. Gruen, Inorg. Chem. 4, 1173 (1965).
A. Barkatt and C. A. Angell, J. Phys. Chem. 79, 2192 (1975).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Savović, J., Nikolić, R. & Veselinović, D. Cobalt(II) Chloride Complex Formation in Acetamide–Calcium Nitrate Tetrahydrate Melts. Journal of Solution Chemistry 33, 287–300 (2004). https://doi.org/10.1023/B:JOSL.0000035361.89473.a4
Issue Date:
DOI: https://doi.org/10.1023/B:JOSL.0000035361.89473.a4