Journal of Analytical Chemistry

, Volume 56, Issue 10, pp 910–917

Determination of Stability Constants of Copper(I) Chelates with 1,10-Phenanthroline by Thermal Lensing

  • S. V. Pakhomova
  • M. A. Proskurnin
  • V. V. Chernysh
  • M. Yu. Kononets
  • E. K. Ivanova
Article

DOI: 10.1023/A:1012301210071

Cite this article as:
Pakhomova, S.V., Proskurnin, M.A., Chernysh, V.V. et al. Journal of Analytical Chemistry (2001) 56: 910. doi:10.1023/A:1012301210071

Abstract

Using investigations of the copper(I)–1,10-phenanthroline system as an example, it is shown that thermal lensing can be used for determining stability constants at a level of concentrations one–two orders of magnitude lower compared to conventional spectrophotometry, with better precision of measurements. The values of stability constants are logβ2= 11.7 ± 0.7 without regard for stepwise chelation, and logK1= 5.9 ± 0.3, logK2= 5.4 ± 0.3, and logβ2= 11.3 ± 0.6 taking into account stepwise chelation. It is shown that, when shifting from microgram to nanogram amounts of reactants in the determination of stability constants by thermal lensing, changes in the kinetic parameters of the reaction studied should be taken into account. The thermal-lens limit of detection of copper(I) is 2 × 10–8M; the linear calibration range is 4 × 10–8–2 × 10–5M (488.0 nm, pump power 120 mW). The data obtained were used for determining copper(I) in the hydrogen sulfide layer of the Baltic Sea.

Copyright information

© MAIK “Nauka/Interperiodica” 2001

Authors and Affiliations

  • S. V. Pakhomova
    • 1
  • M. A. Proskurnin
    • 1
  • V. V. Chernysh
    • 1
  • M. Yu. Kononets
    • 1
  • E. K. Ivanova
    • 1
  1. 1.Chemistry DepartmentMoscow State UniversityVorob'evy gory, MoscowRussia