Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States.
Inorg Chem. 2013 Feb 18;52(4):1965-75. doi: 10.1021/ic302309z. Epub 2013 Jan 29.
The reactions of Ln(2)O(3)/CeO(2)/Pr(6)O(11) (Ln = La-Nd, Sm), molten boric acid, and concentrated HBr or HI result in the formation of La[B(7)O(10)(OH)(3)(H(2)O)Br], Ln[B(6)O(9)(OH)(2)(H(2)O)(2)Br]·0.5H(2)O (Ln = Ce, Pr), Nd(2)[B(12)O(17.5)(OH)(5)(H(2)O)(4)Br(1.5)]Br(0.5)·H(2)O (NdBOBr), Sm(4)[B(18)O(25)(OH)(13)Br(3)], and Ln[B(7)O(11)(OH)(H(2)O)(3)I] (Ln = La-Nd, Sm). The lanthanide(III) centers in these compounds are found with 9-coordinate hula hoop or 10-coordinate capped triangular cupola geometries, where there are six approximately coplanar oxygen donors provided by the polyborate sheet. The sheets are formed into three-dimensional frameworks via BO(3) triangles that are roughly perpendicular to the layers. Additionally, a new cationic framework, NdBOBr, has been isolated. NdBOBr is unusual in that not only is it a cationic framework, but it is also the first trivalent f-element borate to have terminal halides bound exclusively to the base site of the hula hoop. The Ln[B(7)O(11)(OH)(H(2)O)(3)I] (Ln = La-Nd, Sm) structures require two corner-shared BO(3) units in order to tether the layers together because of the large size of the capping iodine atom.
Ln(2)O(3)/CeO(2)/Pr(6)O(11)（Ln = La-Nd，Sm）、熔融硼酸和浓 HBr 或 HI 的反应导致生成 La[B(7)O(10)(OH)(3)(H(2)O)Br]、Ln[B(6)O(9)(OH)(2)(H(2)O)(2)Br]·0.5H(2)O（Ln = Ce，Pr）、Nd(2)[B(12)O(17.5)(OH)(5)(H(2)O)(4)Br(1.5)]Br(0.5)·H(2)O（NdBOBr）、Sm(4)[B(18)O(25)(OH)(13)Br(3)]和 Ln[B(7)O(11)(OH)(H(2)O)(3)I]（Ln = La-Nd，Sm）。这些化合物中的镧系（III）中心具有 9 配位的呼啦圈或 10 配位的盖帽三角顶杯几何形状，其中由多硼酸盐片提供六个大致共面的氧供体。通过大致垂直于层的 BO(3)三角形，将这些薄片形成三维框架。此外，还分离出一种新的阳离子框架 NdBOBr。NdBOBr 很不寻常，不仅它是一个阳离子框架，而且它还是第一个具有端基卤化物仅结合到呼啦圈基底位置的三价 f 系硼酸盐。Ln[B(7)O(11)(OH)(H(2)O)(3)I]（Ln = La-Nd，Sm）结构需要两个共用角的 BO(3)单元来将层连接在一起，因为盖帽碘原子的尺寸较大。
