LAPODS: a computer program for refinement of lattice parameters using optimal regression

Abstract

LAPODSis an upgraded version of the programLAPODfor the refinement of lattice parameters using the method of Cohen [Langford (1971).J. Appl. Cryst.4, 259–260]. The improved version has a number of advanced features. It can detect the most significant systematic errors automatically by means of a statisticalFtest; it can also operate in a manual mode with corrections set by the user or input manually. The single-value decomposition (SVD) method is used so that the refinement is now more stable. The general formula to calculate the specimen-transparency error has been incorporated and a transparency correction can now be made when the absorption is intermediate between the limiting cases of `thick' or `thin' samples.