Journal of Solid State Chemistry ( IF 3.3 ) Pub Date : 2020-01-17 , DOI: 10.1016/j.jssc.2020.121198 Paula Kayser , Hannah E. Johnston , Mu- Hai Fang , David A. Keen , Ru Shi Liu , J. Paul Attfield
The N/O anion distributions in the melilite-type phosphor host material Y2Si3O3N4 and a Ce-doped sample Y1.5Ce0.5Si3O3N4 have been determined from powder neutron diffraction. Both materials have a highly ordered N/O distribution that is not changed significantly by the disorder introduced by Ce doping. This distribution evidences the presence of SiN3O and SiN2O2 tetrahedra and although these are not fully long range-ordered, local structural correlations follow simple connectivity rules that lead to an estimated residual molar entropy of R ln3. A broad range of N/O environments is found around 8-coordinate Y(Ce) sites which is expected to broaden their spectroscopic features.
中文翻译:
硅质磷光体中相关的N / O阴离子级数
由粉末中子衍射求出了陨石型荧光体主体材料Y 2 Si 3 O 3 N 4和Ce掺杂样品Y 1.5 Ce 0.5 Si 3 O 3 N 4中的N / O阴离子分布。两种材料都具有高度有序的N / O分布,不会因Ce掺杂引入的无序而显着改变。该分布证明存在SiN 3 O和SiN 2 O 2四面体,尽管它们不是完全长程的,但局部结构相关性遵循简单的连通性规则,从而导致估计的R ln3残余摩尔熵。在8坐标Y(Ce)站点附近发现了各种各样的N / O环境,有望扩大它们的光谱特性。