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Updated: Jun 2, 2026
09:45
Epitaxial Growth of Perovskite Strontium Titanate on Germanium via Atomic Layer Deposition
Published on: July 26, 2016
Poly[μ-aqua-μ(4)-terephthalato-strontium]
Acta Crystallographica. Section E, Structure Reports Online
|April 28, 2011
Summary
This study details the crystal structure of a strontium terephthalate compound. The strontium ions form an eight-coordinate complex, leading to a 3D framework via linked polyhedra and hydrogen bonds.
Area of Science:
- Inorganic Chemistry
- Crystallography
- Materials Science
Background:
- Metal-organic frameworks (MOFs) and coordination polymers are widely studied for their diverse structures and potential applications.
- Strontium (Sr) compounds, particularly those involving carboxylate ligands, exhibit unique coordination geometries and network topologies.
- Terephthalate ligands offer versatile coordination modes, enabling the formation of extended structures.
Purpose of the Study:
- To elucidate the crystal structure and coordination environment of a novel strontium terephthalate coordination polymer.
- To investigate the self-assembly process and the resulting three-dimensional framework architecture.
- To identify and analyze the intermolecular interactions, such as hydrogen bonding, within the crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the precise atomic arrangement and coordination geometry.
- Analysis of bond distances, angles, and coordination numbers of the central strontium ion.
- Identification of bridging and chelating carboxylate groups and water molecules coordinating to the strontium center.
Main Results:
- The strontium(II) ion displays a coordination number of eight, coordinated by six oxygen atoms from terephthalate ligands and two water molecules.
- The SrO(8) polyhedra link via shared oxygen atoms to form inorganic chains along the b-axis.
- These chains assemble into layers in the ab plane through O-C-O linkages, further connected by terephthalic groups into a 3D framework with observed O-H⋯O hydrogen bonds.
Conclusions:
- The title compound, [Sr(C(8)H(4)O(4))(H(2)O)](n), represents a novel 3D coordination framework built from strontium ions and terephthalate ligands.
- The observed coordination number and linking modes of the strontium polyhedra dictate the formation of the extended inorganic-organic hybrid structure.
- Hydrogen bonding plays a crucial role in stabilizing the overall three-dimensional architecture.
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