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Identification of Multiphase Unknowns by Computer Methods: Role of Chemical Information, the Quality of X-Ray Powder Data and Subfiles

Published online by Cambridge University Press:  06 March 2019

Gregory J. McCarthy  and
Gerald G. Johnson Jr.
Gregory J. McCarthy
Affiliation:
Materials Research Laboratory, The Pennsylvania State University, University Park, PA 16802
Gerald G. Johnson Jr.
Affiliation:
Materials Research Laboratory, The Pennsylvania State University, University Park, PA 16802
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Abstract

Three variables in the identification of crystalline multiphase unknowns by computer search/match methods were examined: presence or absence of chemical information; varying quality of d-I diffraction data; use of a large data base vs a data base having about 10% as many entries--both contain the unknown phases. The results showed that the search/match using average quality d-I data with chemical information was quite successful, while that obtained using higher quality d-I data alone missed one of four phases. It took only half the time to obtain the average d-I data plus chemistry as it did to obtain the higher quality data. Searching the smaller data base with the higher quality data alone resulted in an identification of all phases with high reliability.

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 22: Twenty-Seventh Annual Conference on Applications of X-ray Analysis, August 1-4, 1978 , 1978 , pp. 109 - 120
Copyright
Copyright © International Centre for Diffraction Data 1978

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References

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