Experiments performed on the grwth of mixed crystals of rare earth tartrates (Y1-xSmx)2 (C4H4O6)3.zH2O (0≤x≤1) from silica gels at 35~40℃ and 25~30℃ employing single-diffusion technique. are discussed. The crysta...Experiments performed on the grwth of mixed crystals of rare earth tartrates (Y1-xSmx)2 (C4H4O6)3.zH2O (0≤x≤1) from silica gels at 35~40℃ and 25~30℃ employing single-diffusion technique. are discussed. The crystals maintain spherulitic morphology, irrespective of the value of x, concentration of upper and lower reactants, gel pH, gel age and gel temperature. Formation Of Liesegang rings in this system is a temperature dependent phenomenon. It is shown that with the increase of the value of x the system passes from Liesegangring phenomenon to singlezone phenomenon. Operative mechanism of crystallization in the higher (35~40℃) and lower temperature ranges (25~30℃) is explained. Seeded growth experiments indicate the possibility of increasing the size of the spherulites in the gel medium展开更多
文摘Experiments performed on the grwth of mixed crystals of rare earth tartrates (Y1-xSmx)2 (C4H4O6)3.zH2O (0≤x≤1) from silica gels at 35~40℃ and 25~30℃ employing single-diffusion technique. are discussed. The crystals maintain spherulitic morphology, irrespective of the value of x, concentration of upper and lower reactants, gel pH, gel age and gel temperature. Formation Of Liesegang rings in this system is a temperature dependent phenomenon. It is shown that with the increase of the value of x the system passes from Liesegangring phenomenon to singlezone phenomenon. Operative mechanism of crystallization in the higher (35~40℃) and lower temperature ranges (25~30℃) is explained. Seeded growth experiments indicate the possibility of increasing the size of the spherulites in the gel medium
