Determination of lattice parameters with the aid of a computer

Abstract

A least squares method is described which permits the determination of lattice parameters and standard errors for the orthorhombic system and all other crystal systems of higher symmetry. The angular measurements of lines or spots of several different wave lengths may he used. Provision was made for using as many as three separate correction terms for eccentricity, absorption, divergence, and other variables. Experience has indicated that a weighting factor usually gives a better fit with a smaller standard error. Since a problem can be solved in a short time, it is usually advantageous to obtain several solutions to the problem using various combinations of correction terms and weighting factors in order to verify the fitting process and the accuracy of the lattice parameters. (B.O.G.)