کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1331659 | 979012 | 2009 | 6 صفحه PDF | دانلود رایگان |
Single crystals of iron(II) pyroborate, Fe2B2O5, were prepared at 1000–1050 °C under an argon atmosphere. The crystals were transparent, yellowish in color and needle-like or columnar. The crystal structure of Fe2B2O5 was analyzed by single-crystal X-ray diffraction. Refined triclinic unit cell parameters were a=3.2388(2), b=6.1684(5), c=9.3866(8) Å, α=104.613(3)°, β=90.799(2)° and γ=91.731(2)°. The final reliability factors of refinement were R1=0.020 and wR2=0.059 [I > 2σ(I)]. Transmittance over 50% in the visible light region from 500 to 750 nm was observed for a single crystal of Fe2B2O5 with a thickness of about 0.3 mm. The light absorption edge estimated from a diffuse reflectance spectrum was at around 350 nm (3.6 eV). Magnetic susceptibility was measured for single crystals at 4–300 K. Fe2B2O5 showed antiferromagnetic behavior below the Néel temperature, TN≈70 K, and the Weiss temperature was TW=36 K. The effective magnetic moment of Fe was 5.3μB.
View of the crystal structure of Fe2B2O5 using FeO6 octahedra. Fe2B2O5 has a quasi-one-dimensional structure, consisting of an [Fe4O18] unit parallel to the a-axis.Figure optionsDownload as PowerPoint slide
Journal: Journal of Solid State Chemistry - Volume 182, Issue 8, August 2009, Pages 2004–2009