The crystal structure of terbium(III) scandate(III), with ideal formula TbScO3, has been reported previously on the basis of powder diffraction data [Liferovich & Mitchell (2004). J. Solid State Chem. >177, 2188–2197]. The current data were obtained from single crystals grown by the Czochralski method and show an improvement in the precision of the geometric parameters. Moreover, inductively coupled plasma optical emission spectrometry studies resulted in a nonstoichiometric composition of the title compound. Site-occupancy refinements based on diffraction data support the idea of a Tb deficiency on the A site (inducing O defects on the O2 position). The crystallochemical formula of the investigated sample thus may be written as A(□0.04Tb0.96)BScO2.94. In the title compound, Tb occupies the eightfold-coordinated sites (site symmetry m) and Sc the centres of corner-sharing [ScO6] octahedra (site symmetry ). The mean bond lengths and site distortions fit well into the data of the remaining lanthanoid scandates in the series from DyScO3 to NdScO3. A linear structural evolution with the size of the lanthanoid from DyScO3 to NdScO3 can be predicted.
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机译：先前已根据粉末衍射数据报道了具有理想分子式为TbScO3的scan（III）scan（III）的晶体结构[Liferovich＆Mitchell（2004）。 J.固态化学。 > 177 ，2188–2197]。当前数据是从通过Czochralski方法生长的单晶获得的，并显示出几何参数精度的提高。此外，电感耦合等离子体发射光谱法研究导致标题化合物的非化学计量组成。基于衍射数据的位点占用优化可支持A位点Tb缺乏（在O2位置诱导O缺陷）的想法。因此，所研究样品的晶体化学式可以写为 A （□0.04Tb0.96） B ScO2.94。在标题化合物中，Tb占据了八倍坐标位置（位置对称m），Sc占据了角共享[ScO6]八面体的中心（位置对称）。平均键长和位点畸变非常适合从DyScO3到NdScO3系列的其余镧系元素扫描日期的数据。可以预测镧系元素大小从DyScO3到NdScO3的线性结构演变。
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