NEW POLYMORPH OF CaHPO4 (MONETITE): SYNTHESIS AND CRYSTAL STRUCTURE
N. Ouerfelli1,2, M.F. Zid1
1Universite de Tunis El Manar, El Manar II, Tunis, Tunisia najouerf@yahoo.fr 2Universite de Tunis Carthage, BP 64-7021 - Zarzouna (Bizerte), Tunisia
Ключевые слова: calcium hydrogenphosphate, polymorphs, synthesis, single crystal X-ray diffraction, monetite, crystal structure
Страницы: 658-661
Аннотация
A novel form of anhydrous dicalcium phosphate CaHPO4 (monetite) is synthesized hydrothermally and characterized by single crystal X-ray diffraction. It crystallizes in the orthorhombic space group Ccm 21 with a = 6.242(1) Å, b = 6.994(2) Å, c = 7.003(3) Å, V = 305.73(16) Å3 and it has four independent unit formulas in the unit cell ( Z = 4). A three-dimensional crystal structure can be described by {HPO4} n infinite zigzag chains linked by Ca-O bonds. The comparison to the crystal structures of other polymorphs is given.
DOI: 10.15372/JSC20160325 |