Least-Squares Determination of Molecular Structures from Gaseous Electron-Diffraction Data. II. Polynomial Expression of Background

A new least-squares method has been devised for interpreting electron-diffraction data by comparison of an experimental background with a calculated background. The former is derived from an experimental total intensity by assuming a molecular model. The latter is approximated by a polynomial function. A computer program is written to refine structural parameters of a molecule so as to yield a smooth background. The characteristic of the present method is that it does not need any bias depending upon human judgement throughout an analysis. The distinctive features of the procedure are discussed, and the application of this method to structure determination of several molecules is also described.