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INDEX, A Program to Reconcile Powder Diffractograms

Published online by Cambridge University Press:  06 March 2019

Tommy Horn ,
Ron Jenkins  and
Joshua Ladell
Tommy Horn
Affiliation:
Philips Electronic Instruments, Inc., 85 McKee Drive, Mahwah, N. J. 07430
Ron Jenkins
Affiliation:
Philips Electronic Instruments, Inc., 85 McKee Drive, Mahwah, N. J. 07430
Joshua Ladell
Affiliation:
Philips Laboratories, Briarcliff Manor, N.Y. 10510
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Abstract

This paper describes an interactive computer program, INDEX, which was written at Philips Laboratories as part of the software development effort for the APD 3600: Automated Powder Diffractometer. This program reconciles the differences between calculated and observed powder diffractogram “d-spacings” by unit cell parameters refinement and/or correction of observed lines for “significant“ systematic errors. The reconciliation procedures, described below, yield a set of residual differences which may be due to x-ray photon statistics, random gear imperfections, or minor instrumental aberrations. Lattice parameters accuracies of 4-5 parts per 104 can b e obtained routinely on powder diffractometers when systematic effects have been taken into account. The interactive nature of INDEX permits intervention at critical stages where it is most beneficial with a minimal number of keystrokes.

Type
VI. XRD Search/Match Procedures and Automation
Information
Advances in X-Ray Analysis , Volume 25: Thirtieth Annual Conference on Applications of X-ray Analysis, August 3-7, 1981 , 1981 , pp. 267 - 272
Copyright
Copyright © International Centre for Diffraction Data 1981

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