Department of Chemistry and Center for Optical Materials Science and Engineering Technologies (COMSET), Clemson University, Clemson, South Carolina 29634-0973, United States.
Inorg Chem. 2013 Jan 7;52(1):237-44. doi: 10.1021/ic301760a. Epub 2012 Dec 17.
This paper describes the hydrothermal chemistry of alkali hafnium fluorides, including the synthesis and structural characterization of five new alkali hafnium fluorides. Two ternary alkali hafnium fluorides are described: Li(2)HfF(6) in space group P31m with a = 4.9748(7) Å and c = 4.6449(9) Å and Na(5)Hf(2)F(13) in space group C2/m with a = 11.627(2) Å, b = 5.5159(11) Å, and c = 8.4317(17) Å. Three new alkali hafnium oxyfluorides are also described: two fluoroelpasolites, K(3)HfOF(5) and (NH(4))(3)HfOF(5), in space group Fm3m with a = 8.9766(10) and 9.4144(11) Å, respectively, and K(2)Hf(3)OF(12) in space group R3m with a = 7.6486(11) Å and c = 28.802(6) Å. Infrared (IR) spectra were obtained for the title solids to confirm the structure solutions. Comparison of these materials was made based on their structures and synthesis conditions. The formation of these species in hydrothermal fluids appears to be dependent upon both the concentration of the alkali fluoride mineralizer solution and the reaction temperature. Both X-ray and visible fluorescence studies were conducted on compounds synthesized in this study and showed that fluorescence was affected by a variety of factors, such as alkali metal size, the presence/absence of oxygen in the compound, and the coordination environment of Hf(4+).
本文描述了碱金属铪氟化物的水热化学，包括五种新的碱金属铪氟化物的合成和结构表征。描述了两种三元碱金属铪氟化物：空间群为 P31m 的 Li(2)HfF(6)，a = 4.9748(7) Å，c = 4.6449(9) Å；空间群为 C2/m 的 Na(5)Hf(2)F(13)，a = 11.627(2) Å，b = 5.5159(11) Å，c = 8.4317(17) Å。还描述了三种新的碱金属铪氧氟化物：两种氟代铕酸盐，空间群为 Fm3m 的 K(3)HfOF(5)和(NH(4))(3)HfOF(5)，a 分别为 8.9766(10)和 9.4144(11) Å，以及空间群为 R3m 的 K(2)Hf(3)OF(12)，a = 7.6486(11) Å，c = 28.802(6) Å。对标题固体进行了红外(IR)光谱测试，以确认结构解析。基于它们的结构和合成条件对这些材料进行了比较。这些物质在水热流体中的形成似乎取决于碱氟化物矿化剂溶液的浓度和反应温度。对本研究中合成的化合物进行了 X 射线和可见荧光研究，表明荧光受到多种因素的影响，如碱金属尺寸、化合物中是否有氧以及 Hf(4+)的配位环境。
