Related Experiment Video
Updated: Mar 16, 2026
Spark Plasma Sintering Apparatus Used for the Formation of Strontium Titanate Bicrystals
Published on: February 9, 2017
Crystal structure of strontium dicobalt iron(III) tris-(orthophosphate): SrCo2Fe(PO4)3
Adam Bouraima1, Thomas Makani2, Abderrazzak Assani3
1Laboratoire de Chimie du Solide Appliquée, Faculty of Sciences, Mohammed V University in Rabat, Avenue Ibn Battouta, BP 1014, Rabat, Morocco; Département de Chimie, Faculté des Sciences, Université des Sciences et Techniques de Masuku, BP 943, Franceville, Gabon.
Abstract:
The title compound, SrCo2Fe(PO4)3, has been synthesized by a solid-state reaction. It crystallizes with the α-CrPO4 type structure. In this structure, all atoms are on special positions of the Imma space group, except for two O atoms which are located on general positions. The three-dimensional network in the crystal structure is made up of two types of layers stacked normal to (100). The first layer is built from two edge-sharing CoO6 octa-hedra, leading to the formation of Co2O10 dimers that are connected to two PO4 tetra-hedra by a common edge and corners. The second layer results from apex-sharing FeO6 octa-hedra and PO4 tetra-hedra, which form linear chains alternating with a zigzag chain of Sr(II) cations. These layers are linked together by common vertices of PO4 tetra-hedra and FeO6 octa-hedra to form an open three-dimensional framework that delimits two types of channels parallel to [100] and [010] where the Sr(II) cations are located. Each Sr(II) cation is surrounded by eight O atoms.
Related Concept Videos
02:42Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:42Valence Bond Theory
02:34Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
02:48Ionic Bonding and Electron Transfer