Phase identification and qualitative analysis

An automatic search-and-match can be done much faster, and most importantly, using multiple Bragg reflections by seeking through enormous arrays of data, which a typical database contains. The algorithms employed to conduct automatic searches vary extensively, however, parameters that are critical in any search include the following  

Window (or tolerance) - a difference in positions between the observed and database peaks as long as the deviation remains below the tolerance (i.e. within the window), peaks are considered matching. The window may be specified as a range or 20, rf-spacing, or other means commonly used to express peak positions. 

A powerful way to narrow the searching field is to include restrictions on the elemental composition. For example, the list of chemical elements can be specified and used in combination with the following search options  

Inclusive OR limits the search to phases containing at least one of the listed elements and any other elements, not included in the list  

Inclusive AND considers only phases containing all listed elements plus any chemical element not included in the list  

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