Hostname: page-component-76fb5796d-9pm4c Total loading time: 0 Render date: 2024-04-28T10:31:24.623Z Has data issue: false hasContentIssue false

Accurate fully automated powder diffraction data using zero-background sample holders

Published online by Cambridge University Press:  10 January 2013

S. T. Misture
Affiliation:
Institute for Ceramic Superconductivity, New York State College of Ceramics atAlfred University, Alfred, New York 14802
L. R. Chatfield
Affiliation:
Institute for Ceramic Superconductivity, New York State College of Ceramics atAlfred University, Alfred, New York 14802
R. L. Snyder
Affiliation:
Institute for Ceramic Superconductivity, New York State College of Ceramics atAlfred University, Alfred, New York 14802

Abstract

An increasingly frequent used sample holder, the zero-background holder (ZBH), is evaluated for use in external standard calibration of powder patterns. The effectiveness of the ZBH calibration method is determined by comparison to the conventional internal- and external-standard calibration techniques. The three calibration methods are compared using the results of lattice parameter refinements of test powders, using Si as the standard. Several test materials were used in the evaluation which cover a wide range of absorption coefficients so sample transparency effects can be distinguished from sample displacement effects. Results of the calibrations clearly indicate that the ZBH method gives precision and accuracy comparable to the internal-standard method, and significantly better than the external-standard technique. In addition, the ZBH method yields substantially better results than the internal-standard method for materials with low absorption coefficients. Low-angle calibrations are also made on a ZBH using a proposed standard, silver behenate, which has peaks from 1.5° to 20° 2θ. These calibrations have shown that if care is not taken to establish a monolayer of powder on the ZBH crystal, significant errors in refined lattice parameters will result.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1994

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Evens, H. Jr., Appleman, D., and Handwerker, D. (1963). Report PB2-16188, U.S. Dept. of Commerce, National Technical Information Center, Springfield, VA.Google Scholar
Howard, S. A. and Snyder, R. L. (1989). “The Use of Direct Convolution Products in Profile and Pattern Fitting Algorithms I. Development of the Algorithms,” J. Appl. Crystallogr. 22, 238243.CrossRefGoogle Scholar
Huang, T. C., Toraya, H., Blanton, T., and Wu, Y. (1993). “X-ray Powder Diffraction Analysis of Silver Behenate. A Possible Low-Angle Diffraction Standard,” J. Appl. Crystallogr. 26, 180184.CrossRefGoogle Scholar
Hubbard, C. R., Lederman, S. M., and Pyrros, N. P. (1982). JCPDS-NBS*LSQ82, U.S. National Bureau of Standards, Private Communication.Google Scholar
Hubbard, C. R., Robbins, C. R., and Snyder, R. L. (1983). “XRD Quantitative Analysis Using the NBS*QUANT82 System,” Adv. X-ray Anal. 26, 149157.Google Scholar
Jenkins, R., and Schreiner, W. N. (1989). “Intensity Round Robin Report,” Powder Diffr. 4, 74.CrossRefGoogle Scholar
Mallory, C. L., and Snyder, R. L. (1979). “The Control and Processing of Data from an Automated X-ray Powder Diffractometer,” Adv. X-ray Anal. 22, 121132.Google Scholar
Matthews, F. W., Warren, G. G., and Michell, J. H. (1950). Anal. Chem. 22, 514.CrossRefGoogle Scholar
Schreiner, W. N., and Fawcett, T. (1985). “Results of a Round Robin Study of Systematic Errors Found in Routine X-ray Diffraction Raw Data,” Adv. X-ray Anal., 309314.Google Scholar
Smith, G. S., and Snyder, R. L. (1979). “Fn: A Criterion for Rating Powder Diffraction Patterns and Evaluating the Reliability of Powder Pattern Indexing,” J. Appl. Crystallogr. 12, 6065.CrossRefGoogle Scholar
Snyder, R. L., Johnson, Q. C., Kahara, E., Smith, G. S., and Nichols, M. C. (1978). “An Analysis of the Powder Diffraction File,” Lawrence Livermore Laboratory (UCRL-52505).CrossRefGoogle Scholar
Snyder, R. L. (1983a). “Accuracy in Angle and Intensity Measurements in X-ray Powder Diffraction,” Adv. X-ray Anal. 26, 111.Google Scholar
Snyder, R. L. (1983b). “The Renaissance of X-ray Powder Diffraction,” in Advances in Material Characterization, edited by Rossington, D. R., Condrate, R. A., and Snyder, R. L. (Plenum, New York), pp. 449464.CrossRefGoogle Scholar
Wong-Ng, W., and Hubbard, C. R. (1987). “Standard Reference Materials for X-ray Diffraction Part II: Calibration Using d Spacing Standards,” Powder Diffr. 2, 257265.CrossRefGoogle Scholar
Young, L. C. (1941). Ann. of Math. Stat. XII(3), 293300.CrossRefGoogle Scholar