|
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 squares fitting is used, for example, in deconvolutions
of overlapping bands in vibrational or electronic spectra
and in analysis of chemical kinetics. Frequently, fits of
nonlinear equations are done using the GaussNewton
or Marquardt methods (810). However in this work we
use the quasi-Newton method (11).
Literature Cited
1. Rioux, F. J. Chem. Educ.
1991, 68, A282A283.
2. Currie, J. O.; Whiteley, R. V., Jr.
J. Chem. Educ. 1991, 68, 923926.
3. David, C. W. J. Chem. Educ.
1989, 66, A237A238.
4. Simpson, J. M. J. Chem. Educ.
1994, 71, A88A90.
5. O'Connor, S; Bailey, D. J. Chem.
Educ. 1994, 71, A91A92.
6. Gaeng, P. EXCEL for Science and
Technology; Abacus: Grand Rapids, MI, 1993.
7. Freiser, H. Concepts & Calculations in Analytical Chemistry:
A Spreadsheet Approach; CRC: Boca Raton, FL, 1992.
8. Copeland, T. G. J. Chem.
Educ. 1984, 61, 778779.
9. Moore, P. J. Chem. Soc. Faraday Trans.
I, 1972, 18901893.
10. Poshusta, R. D. Comput.
Phys. 1991, 5(2), 248252.
11. Himmelblau, M. D. Applied Nonlinear
Programming; McGraw-Hill: New York, 1972.
12. Militky, J.; Meloun, M.
Talanta 1993, 40, 269277.
|
Citation
