Nonlinear Curve Fitting Using Spreadsheets

Abstract

The use of spreadsheets in chemistry is common, mainly in analytical and physical chemistry, where they are used to calculate systems of linear equations, nonlinear equations using the iterative Newton­Raphson method, linear least squares regressions, etc. All these applications are well described in articles (1­5) and books (6, 7). Besides calculational facilities, commercial spreadsheets also have advanced numerical tools packages that allow sophisticated calculations in multivariate statistics, as well as linear and nonlinear optimizations, Fourier transforms, and much more. These packages often contain graphical facilities that allow 2D and 3D graphics of functions and discrete point sets. However, finding these tools is not easy, because they are usually not readily apparent from the documentation accompanying the programs. The goal of this article is to emphasize the capabilities of spreadsheets in solving specific problems common in chemistry, such as nonlinear curve fitting. Nonlinear least square...