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Updated: Oct 11, 2025
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
New iodine-apatites: synthesis and crystal structure
Evgeny N Bulanov1, Sergey S Petrov1, Alexander V Knyazev1
1Department of Analytical and Medicinal Chemistry, Faculty of Chemistry, Lobachevsky University, Nizhny Novgorod Russia.
Abstract:
The paper describes methods for the preparation of compounds with an apatite structure containing only iodine atoms in the "halogen" position. The crystal structure of the compounds was refined by the Rietveld method. The resulting apatites have a structure with a space group P63/m and have the following unit cell parameters: Ba4 1.78(2)Ba6 2.75(2)(PO4)3I0.04(2) (a = 10.18609(34) Å, c = 7.71113(30) Å, V = 692.889(54) Å3, R = 5.448 %), Pb4 1.82(2)Pb6 2.75(2)(PO4)3I0.13(2) (a = 9.87882(18) Å, c = 7.43222(16) Å, V = 628.144(26) Å3, R = 8.533 %), Pb4 1.90(2)Pb6 2.68(2)(PO4)3I0.16(2) (a = 9.87058(48) Å, c = 7.41255(46) Å, V = 625.437(72) Å3, R = 5.433 %). The study of the crystal structure showed a relatively low efficiency of the binding of iodine in the apatite matrix.
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