Investigation of lithium silicate compounds stability by means of x-ray diffraction method (XRD)

In this work، the comprision of phase stability of lithium silicates in the ratios of Li: Si 1:2 and 1:3 from the raw materials of lithium nitrate and silicic acid and in the ratio of Li: Si 1:2 from the raw materials of lithium sulphate and silicic acid in the temperatures of 48، 72، 96 and 120 h with using x-ray diffraction method was performed. Also، we calculated inter planar spacing (d) of the synthesized materials with using Braggs equation. Synthesized materials sizes were calculated via scherrer equation in different phases and in different Li: Si molar ratios. Cell parameters of lithium metasilicate are a=9. 392، b=5. 397 and c=4. 66 Å and the parameters for lithium disilicate are a=15. 82، b=14. 66 and c=4. 79Å. Cell parameters of lithium sodium silinaite are a=5. 06، b=8. 23 and c=14. 38Å with space group of A2/n. Results show that lithium metasilicate and lithium disilicate have space groups of Cmc21 and Ccc2، respectively.