Dear Farid Dris sorry to see that your interesting technical question has not yet been answered by experts. If you have metallic yttrium available, you can indeed dissolve it in aqueous HCl and evaporate the resulting solution to dryness. A cheaper and more economical way to synthesize yttrium trichloride would start from readily available yttrium oxide. Yttrium oxide (Y2O3) is the most common and easiest accessible starting material for preparing other yttrium compounds. You can saturate a boiling aqueous hydrochloric acid with yttrium oxide until no more oxide dissolves. Then filter the solution while hot and concentrate the filtrate on a hot plate until the first solid appears on the surface. Then let the solution cool to toom temperature over night. This will give you crystalline yttrium trichloride hexahydrate in high yield.

Good luck with your work and best wishes, Frank Edelmann

Dear Farid Dris P.S. Here too I would strongly suggest to you that you edit your original question and correct the typing errors ("How to form yttrium chloride?"). It's very easy to do. Just go to the question page and click on the down arrow in the upper right corner. Then click on "Edit" and make the appropriate corrections. Your question will look much better when it is error-free. After all, you want to make a professional impression on other RG members, right?

With best wishes, Frank Edelmann