Program seppeak 1.1: Separator of overlapping peaks

Computers Chem. Vol. 19, No. 4, p. 435, 1995 Copyright 0 1995 Elder Science Ltd Printed in Great Britain. All rights reserved

Pergamon

0097-8485/95 s9.50 + 0.00

SOFTWARE NOTE PROGRAM

SEPPEAK WEIGUANG

1.I: SEPARATOR PEAKS HUANG

OF OVERLAPPING

and BRYNN HIBBERT

School of Chemistry, University of New South Wales. Sydney, NSW 2052, Australia (Received 20 February 1995)

(3) the calculated values of the standard rate constant for the quasi-reversible; and (4) statistical data, e.g. the relative standard deviation RSD as a measurement of goodness of fit, the number of iterations, etc.

SepPeak is a software package to enable separation of overlapping peaks. The program extracts signals of individual components from overlapping peaks with background and noise by curve fitting. It can separate the overlapping peaks with a peak location difference as small as 1 mV. To fit a set of one or more theoretical peak shapes to a set of experimental data, users may select a single type or mixed types of the peak shapes. There are three available types of peak shape; they are:

It will output a graph of the individual peaks, zoom in and out within graphics, and locate any point of a peak, by interfacing with the software PlotData (a software plotter). It offers an interactive menu environment, runs on an IBM-PC under MS-DOS, and the easy to use. SepPeak has been successfully applied to a wide range of voltammetric peaks [e.g. In(II1) + Cd(H), Pb(I1) + TI(I), Cr(II1) + Zn(II), and binuclear copper complexes in aqueous and non-aqueous media] by various electrochemical techniques (e.g. differential pulse, square wave, pseudo-derivative normal pulse voltrammetry) (see all Refs). It is available from the author.

(1) reversible peak;

(2) irreversible peak; (3) quasi-reversible peak. The reversible peak shape is symmetric, but the irreversible and quasi-reversible peak shapes are asymmetric. Peak shape (1) has two or three unknown parameters. If the value of the half-peak width is not exactly equal to the theoretical value of the half-peak width (which usually occurs in practice), the half-peak width is taken as an unknown parameter in addition to the peak height and the peak location. Peak shape (2) has three unknown parameters: the peak height, the peak location, and the charge transfer coefficient (related to the peak width). Peak shape (3) has four unknown parameters: three of them are the same as peak shape (2) plus the standard rate constant (related to symmetry). SepPeak outputs the following information:

REFERENCES

Bond A., Huang W. & Oldham K. (1988) Proc. 7th Australian Electrochem. Conf., University of New South

Wales, Sydney, Australia, p. 383. Bond A., Huang W., Henderson T. & Oldham K. (1990) Proc. Chinese Chemistry Symp., La Trobe University, Melbourne, Australia, pp. 8-9. Huang W. (1990) Ph.D. Thesis, Deakin University, Geelong, Austraha, pp. l-305. Huana W.. Hibbert B. & Bond A. (1994) Proc. 9th A&al& Electrochem. ConjI, University of Wollongong, Wollongong, Australia, pp. 75.1-75.3. Huang W., Henderson T., Bond A. M. & Oldham K. B. (1995) Anal. Chim. Acfa 304, l-15.

(1) the calculated values of the peak height, location and width; (2) the calculated values of the charge transfer coefficient for the irreversible peak;

435