首页> 外文期刊>International Journal of Quantum Chemistry >Synthesis, crystal structure and charge distribution of Na7As11O31: An oxygen-deficient layered sodium arsenate
【24h】

Synthesis, crystal structure and charge distribution of Na7As11O31: An oxygen-deficient layered sodium arsenate

机译:缺氧层状砷酸钠Na7As11O31的合成,晶体结构和电荷分布

获取原文
获取原文并翻译 | 示例
           

摘要

A new sodium arsenate with layer structure has been synthesized and its crystal structure solved and refined by single-crystal X-ray diffraction. The crystal is trigonal, space group P (3) over bar m1, a = 11.199(3) angstrom, c = 5.411(2) angstrom, V = 587.80(3) angstrom(3), Z = 1; the refinement converged to R = 0.0282 and wR = 0.0751 for 590 reflections with (I) > 2sigma(I). The structural model gives the formula Na7As11O32, which would be non-neutral; besides, the structural model is not validated by the charge distribution (CD) analysis, which gives an unsatisfactory agreement on the computed charges of the cations. The CD analysis suggest incomplete (5/6) occupation of the O5 site, which leads to the deficiency of an oxygen atom per unit cell and to formula Na7As11O31: this new structural model corresponds to a neutral compound, is validated by the CD analysis, and results in better displacement parameters for O5 than its non neutral counterpart. The (001) anionic layers are built up from corner and edge sharing of As1 and As2 distorted octahedra and As3 distorted tetrahedra, the sodium cations playing the role of interlayer cations. The effects of the oxygen deficiency on the crystal structure are discussed. (c) 2006 Elsevier Inc. All rights reserved.
机译:合成了一种具有层结构的新型砷酸钠,并通过单晶X射线衍射对其晶体结构进行了解析和精制。晶体是三角形的,在m1上的空间群P(3),a = 11.199(3)埃,c = 5.411(2)埃,V = 587.80(3)埃(3),Z = 1;对于(I)> 2sigma(I)的590次反射,细化收敛到R = 0.0282和wR = 0.0751。结构模型给出的公式为Na7As11O32,它是非中性的。此外,结构模型未通过电荷分布(CD)分析验证,这对阳离子的计算电荷给出了不令人满意的协议。 CD分析表明O5位置不完全(5/6)占据,这导致每个晶胞缺乏氧原子,分子式为Na7As11O31:这种新的结构模型对应于中性化合物,通过CD分析得到了验证,并导致O5的位移参数比其非中性对应物更好。 (001)阴离子层是由扭曲的As1和As2的八面体和扭曲的As3和四面体的As3和As3的角和边缘共享建立的,钠阳离子起层间阳离子的作用。讨论了缺氧对晶体结构的影响。 (c)2006 Elsevier Inc.保留所有权利。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号