Mild Hydrothermal Synthesis of Cu(SeO₃).2H₂O: Structural Characterization, Thermal, Spectroscopic and Magnetic Studies

详细信息    查看全文

• 作者：Aitor Larrañ ; aga ; José ; L. Mesa ; Luis Lezama ; Marí ; a I. Arriortua ; Teó ; filo Rojo
• 关键词：Hydrothermal synthesis ; Cu(II) selenite ; Thermal study ; IR and UV-Vis spectroscopies ; ESR ; Magnetism
• 刊名：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
• 出版年：2009
• 出版时间：March 2009
• 年：2009
• 卷：72
• 期：2
• 页码：356-360
• 全文大小：757 K

文摘

Cu(SeO₃).2H₂O has been synthesized by hydrothermal technique under autogeneous pressure. The compound crystallizes in the P2₁2₁2₁ orthorhombic space group. The unit cell parameters are a = 6.672(1), b = 9.167(1) and c = 7.372(1) Å with Z = 4. The crystal structure has been refined using the Rietveld method. The limit of thermal stability is 130 °C, temperature at which the water content is lost. Above 470 °C the compound decomposes in SeO₂(g) and CuO(s). The IR spectrum shows the characteristic bands of the (SeO₃)²⁻ oxoanion and water molecules. An intense absorption band characteristic of Cu(II) cations in five-coordination is observed in the diffuse reflectance spectrum. The ESR spectra are isotropic from room temperature to 4.2 K, with g = 2.13(1). Magnetic measurements confirm the existence of a global antiferromagnetic behavior with a spin canting phenomenon detected at, approximately, 30 K.