金红石型结构的微变化几何学

MICROVARIED GEOMETRY OF THE RUTILE TYPE STRUCTURE

根据金红石型结构中各离子的几何关系,从理想的等键长型结构开始,通过对各个方向的变形计算得出各个离子在不同变形情况下的几何关系。最后总结出在实际的晶体结构中c/a轴比与O^(2-)参数u的关系,并推导出在a、c已知的情况下,O^(2-)参数u的计算方法, u=0.353 6 c/[a·sin(2∠~1±δ)]或u=0.5-{(0.353 6 c)/[a·tan(2∠~1±δ)]}。

In this paper, the general geometrical relations between the every ions of the Rutile typt structure were discussed, in considerable detail. The relations between the c/a axial ratio and the u value of O^(2-) ion, in the equal bond length type crystal structured in terms of theory, and the true crystal tsructure were deduced, too. The calculating formula of the u value of the O^(2-) ions of the Rutile type. structure were presented. There are: u=0.353 6c)/[a·sin(2∠1±δ)]or u=0.5- {(0.353 6c)/[a·tan(2∠1±δ)]}.