I made zinc hydroxide/PVA composite. I did Xrd. Acording to JCDPS Some peaks match with wülfingite and other with sweetite.How to explain the crystal structure of Zn(OH))2.
Zinc hydroxide Zn(OH)2 has three natural mineral named wülfingite (orthorhombic), ashoverite and sweetite (both tetragonal).
Sometimes one can never find a homogenius structure, and other phases are called as "impurity" phases. But I dont know how to determine.
your synthesis was not complete. You should work more on your synthesis process and change the conditions in order to make only one phase crystal.
When you use a diffraction pattern matching software such as Match (R), your xrd data may match with many (several hundreds) minerals. That does not mean the structure of your sample contains all or some of these structures. These matching structures are just possible candidates that your sample may have. hence, using the data (structural parameters) of the most likely structure you should explore your data deeply by using programs like FullProf (doing Rietveld refinement). Of cource, it is possible that your sample might consist of more that single crystallographic phase
It shows that your synthesis was not complete, you have mixture of the both.
When your phase is not pure and if you know the source of impurity, then you also have crystal structure of impure phase too, then but using refinement such as GSAS or Fullproof software you can calculate the percentage of each one. For example it tells you have 80% wulfingite and 20% sweetite
First of all, you have to decompose the peaks of your XRPD diagram. The match of the maxima of the peaks with the theoretical diffraction lines of a given compound are not sufficient to identify a crystal phase. Then you should eliminate the peaks that can be attributed, with certainty, to a given crystal phase .
In the attachment I send you a paper in which there is a good example of peak decomposition: one can separate two crystal phases which were mixed during the precipitation.
If you are interested to a decomposition program, please do not hesitate to contact me.
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