Overall stability constants and thermodynamic parameters of various metal 8-quinolinethiolato complexes in nonaqueous solvents
✍ Scribed by Yasuo Nakabayashi; Yoshitaka Masuda; Eiichi Sekido
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- English
- Weight
- 448 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0013-4686
No coin nor oath required. For personal study only.
✦ Synopsis
The overall stability constants of various metal &quinolinethiolato complexes ([M(c&]; M = Mn, Co, Ni, Cu, Zn, Cd, Hg) in DMSO have been obtained by a combination of the polarography of the sodium salt of I-quinolinethiol and the potentiometry with a mercury electrode based on the determination of the position of exchange equilibria of the ty& [Hg(qt),] + M*+ +[M(qt)2] +Hgs+. The stability sequence of Mn(II) to Zn(I1) complexes was in agreement with Irving-Williams series. Enthalnies and entropies of the complex formation have been also evaluated from the effect of temperature on tbk overall stability constants. Enthalpies of Mn(II) to Zn(I1) complexes were dominated in relation to the overall stability constants and entropies were almost the samevalues. The overall stability constants of Zn(II), Cd(II), and Hg(I1) complexes, however, were contributed to both parameters. Enthalpies of all complexes depended linearly on the softness of metal ions. A nearly linear relationship was found between the logarithmic overall stability constant of [Zn(qt)J and the donor numbers of the solvents.