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We have just released the new Match! version 4 that provides profile fitting search-match as an alternative to the proven peak-based search-match function for qualitative analysis.

 

The good news first: All Match! version 3 customers whose update permission time has not expired yet can update to the new version 4 free-of-charge! Hence, if you are a licensed user of the previous version 3, please check your update permission time (e.g. in "Help / About Match!")

 

In addition, everybody can try the new version 4 for two months free-of-charge, even you don't have a license for Match! so far and the previous demo version 3 has already expired!

 

 

Here is what's new in version 4:

 

Profile Fitting Search-Match

 

The main improvement is the so-called "profile fitting search-match" (PFSM), a powerful, innovative alternative to the proven peak-based search-match functionality for qualitative phase analysis. The new function fits the profile calculated from each candidate entry of the current reference database (or answer set) to the experimental profile on the fly, so that the sometimes ambiguous peak searching is no longer required for qualitative phase analysis.

 

The new feature works without additional software, i.e. no Rietveld software (like FullProf) is required! In fact, no Rietveld refinement is performed actually, because no structural parameters are refined.

 

Here is how it works: During profile fitting search-match, Match! calculates a profile pattern for every entry of the reference database (or answer set), and fits both the intensity scale factor as well as the 2theta shift in order to get an optimum agreement with the experimental profile diffraction pattern. The candidate entries are ranked according to the Rwp values resulting from the individual fitting calculations, or, to be exact, to the reduction of the Rwp value D(Rwp) calculated from the selected phases that the corresponding new candidate entry would achieve.

 

The main advantage of profile fitting search-match (PFSM) is the fact that no peak searching is required, thus avoiding the ambiguities that may arise from this.

 

Another important advantage (compared to the Rietveld refinement search-match approaches cited below) is that PFSM in Match! can use any conventional peak data reference databases, like the COD, ICDD PDF-2, PDF-4, own diffraction patterns etc. The knowledge of atomic parameters for the candidate phases is not required!

 

While the success rate of this new approach is definitely higher than the "classical" (peak-based) approach (especially with minor or trace phases), there is certainly one main drawback: The calculation time is significantly longer. In order to compensate for this to a certain degree, the profile fitting search-match by default runs in parallel on all available cores of your CPU. It is also possible to restrict the calcuation to a lower number of CPU cores (or even to a single core), in order to keep your computer more "responsive" for other tasks.

 

Here is a screenshot of the new version, showing the new profile fitting search-match function in action on a Cement sample:

 

Screenshot v4 Cement Sample

 

Further Improvements in Match! 4

In addition to profile fitting search-match, Match! version 4 provides quite a lot of other significant improvements: