eng Ansari Education and Research Society Journal of Ultra Chemistry 0973-3450 2319-8036 August 2010 6 2 161 170 juc 609 article AYI A. AYI (ay_72000@yahpp.com) 1 Bassey Inah ( ayiayi71@gmail.com) 1 Materials Chemistry Unit, Department of Pure and Applied Chemistry University of Calabar P.M.B. 1115-Calabar (NIGERIA) <p style="text-align: justify;">Single crystals of rare-earth selenate-selenite of composition: Nd₂(SeO₄)₂(SeO₃) (H₂O) was obtained by interaction of amine-selenate monohydrate<strong> </strong>[NH₃(CH₂)₂NH₂(CH₂)₂ NH₂(CH₂)₂NH₃ ]_0.5[SeO₄] .H₂O<strong> </strong>with Nd³⁺ ions followed by hydrothermal processing at 150^oC. The material crystallizes in the monoclinic space group P2₁/c with the following cell parameters: a = 10.608(2), b = 13.951(3), c = 9.799(3)&Aring;, &acirc;= 93.12(2)^o. The infrared spectrum clearly shows the presence of coordinated water molecule. The absorption bands at 3508cm^-1and 3348cm^-1corresponds respectively to asymmetric and symmetric stretching vibrational modes of ligated water molecule. The absorption band at 1630cm^-1 is attributed to the bending vibrational mode of the aqua ligand. The absorption bands at 878, 913 and 962cm^-1 are assigned to &otilde;_(Se-O) vibrations. The material is stable up to 180^oC. The first weight loss of 2.64% (Calc 2.56%) in the region 180-250^oC is indicative of the removal of one molecule of coordinated water. The second weight loss of 16.66 %(Calc16. 23 %) in the region 600-650^oC corresponds to the loss of SeO₂.</p> https://journalofchemistry.org/paper/609/ amine-selenate selenate-selenite frameworks hydrothermal processing