Composition and stability constants of copper(II) complexes with succinic acid determined by capillary electrophoresis |
| |
| Authors: | Viktoria V Sursyakova Galina V Burmakina Anatoly I Rubaylo |
| |
| Institution: | 1. Laboratory of molecular spectroscopy and analysis, Institute of Chemistry and Chemical Technology of the Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk, Russiaviktoria_vs@list.ru;3. Laboratory of molecular spectroscopy and analysis, Institute of Chemistry and Chemical Technology of the Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk, Russia;4. School of Non-Ferrous Metals and Material Science, Siberian Federal University, Krasnoyarsk, Russia;5. Krasnoyarsk Science Center of the Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk, Russia |
| |
| Abstract: | The advantage of capillary electrophoresis was demonstrated for studying a complicated system owing to the dependence of direction and velocity of the electrophoretic movement on the charge of complex species. The stability constants of copper(II) complexes with ions of succinic acid were determined by capillary electrophoresis, including the 1?:?2 metal to ligand complexes which are rarely mentioned. The measurements were carried out at 25 °C and ionic strength of 0.1, obtained by mixing the solutions of succinic acid and lithium hydroxide up to pH 4.2–6.2. It was shown that while pH was more than 4.5 the zone of copper(II) complexes with succinate moves as an anion. It is impossible to treat this fact using only the complexes with a metal-ligand ratio of 1?:?1 (CuL0, CuHL+). The following values of stability constants were obtained: log β(CuL) = 2.89 ± 0.02, log β(CuHL+) = 5.4 ± 0.5, log β(CuL22?) = 3.88 ± 0.05, log β(CuHL2?) = 7.2 ± 0.3. |
| |
| Keywords: | Succinic acid capillary electrophoresis stability constant Cu(II) complexes charge of complex |
|
|
