# PSEQUAD

A Comprehensive Program for the Evaluation of Potentiometric and/or Spectrophotometric Equilibrium Data Using Analytical Derivatives

Chapter

## Abstract

Potentiometry and spectrophotometry are the most frequently used experimental methods to study equilibrium systems in solutions; these methods may be used in many different types of experimental arrangements. The equilibrium system can be described through the mass-balance equations as where

$$ {C_{1}} = \sum\limits_{{j = 1}}^{n} {{\alpha _{{jk}}}\left[ {{S_{j}}} \right] = \quad \sum\limits_{{j - 1}}^{n} {{\alpha _{{jk}}}{\beta _{j}}\prod\limits_{{i = 1}}^{k} {{{\left[ {{c_{i}}} \right]}^{{\alpha ji}}}} } } $$

(1)

*n*is the number of species in the system, including the components;*S*_{ j }is the*j*th species present in the system;*k*is the number of components in the system; [c_{1}] ... [c_{ k }] is the equilibrium (free) concentration of the components; \( {\beta _j} = \left[ {{S_j}} \right]/\left( {\prod\nolimits_{i = 1}^k {{{\left[ {{c_i}} \right]}^{\alpha ji}}} } \right) \), the formation constant of the species, (the formation constants of the components are unity);*α*_{ ji }are stoichiometric numbers, giving the number of the*i*th component in the*j*th species.## Keywords

Titration Curve Molar Absorptivity Formation Constant Equilibrium Data Analytical Derivative
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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## References

- 1.G. E. Forsythe and C. B. Moler,
*Computer Solution of Linear Algebraic Systems*, Prentice-Hall, Englewood Cliffs, New Jersey [Hungarian translation, Müszaki Könyvkiadö, Budapest, (1976)].Google Scholar - 2.W. R. Smith, The Computation of Chemical Equilibria in Complex System,
*Ind. Eng. Chem. Fundam.***19**, 1–10 (1980).CrossRefGoogle Scholar - 3.A. A. Bugaevsky and B. A. Dunai, Calculation of the Equilibrium Composition and Buffer Properties of Solutions with the Use of Computers (in Russian),
*Zh. Anal. Khim.***26**, 205–209 (1971).Google Scholar - 4.A. A. Bugaevsky, L. E. Rudnaya, and T. P. Mukhina, Calculation of Equilibria in Complex Systems (in Russian),
*Zh. Anal. Khim.***27**, 1675–1679 (1972).Google Scholar - 5.A. A. Bugaevsky and L. E. Nikishina, On the Analytical Method of Calculating the Derivatives of Equilibrium Concentrations,
*Talanta***28**, 977 (1981).CrossRefGoogle Scholar - 6.I. Nagypál, I. Páka, and L. Zékány, Analytical Evaluation of the Derivatives Used in Equilibrium Calculations,
*Talanta***25**, 549–550 (1978).CrossRefGoogle Scholar - 7.J. M. Ortega and W. C. Rheinboldt,
*Iterative Solution of Nonlinear Equations in Several Variables*, Academic Press, New York (1970).Google Scholar - 8.Yu. V. Linnik,
*Method of Least Squares and Principles of the Theory of Observations*, Pergamon Press, Oxford (1961).Google Scholar - 9.L. G. Sillén and B. Warnqvist, High-speed Computers as a Supplement to Graphical Methods. 6. A Strategy for Two-level LETAGROP Adjustment of Common and “Group” Parameters. Some features that avoid divergence.
*Ark. Kemi***31**, 315–339 (1969).Google Scholar - 10.R. H. Barham and W. Drane, An Algorithm for Least Squares Estimation of Nonlinear Parameters When Some of the Parameters are Linear,
*Technometrics***14**, 757–766 (1972).CrossRefGoogle Scholar - 11.A. D. Zuberbuhler and Th. A. Kaden, TITFIT, A Comprehensive Program for Numerical Treatment of Potentiometric Data using Analytical Derivatives and Automatically Optimized Subroutines with the Gauss-Newton-Marquardt Algorithm,
*Talanta***29**, 201–206 (1982).CrossRefGoogle Scholar - 12.A. Sabatini, A. Vacca, and P. Gans, MINIQUAD—A General Computer Programme for the Computation of Formation Constants from Potentiometric Data,
*Talanta***21**, 53–77 (1974).CrossRefGoogle Scholar - 13.H. M. Irving, M. G. Miles, and L. D. Pettit, A Study of Some Problems in Determining the Stoicheiometric Proton Dissociation Constants of Complexes By Potentiometric Titrations Using a Glass Electrode,
*Anal. Chim. Acta***38**, 475–488 (1967).CrossRefGoogle Scholar

## Copyright information

© Plenum Press, New York 1985