Metal-Ligand Polyhedra: Difference between revisions
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Shown at right (<scene name='Metal-Ligand_Polyhedra/Polyhedron_main_chains/7'>restore initial scene</scene>) is the "main chain" of a crystallographic model for the largest such structure reported as of May, 2010<ref name="sun-fujita-2010" >PMID: 20430973</ref>. <scene name='Metal-Ligand_Polyhedra/Polyhedron_main_chains/10'>24 palladium ions</scene> form the vertices of a 26-face polyhedron<ref>M24L48 forms a 26-faced ''rhombicubooctahedron'' with 18 square faces and 8 triangular faces. In this instance, the rectangular faces are very close to squares 13.35 Ångstroms on a side.</ref>. Three square faces and one triangular face meet at each vertex. | Shown at right (<scene name='Metal-Ligand_Polyhedra/Polyhedron_main_chains/7'>restore initial scene</scene>) is the "main chain" of a crystallographic model for the largest such structure reported as of May, 2010<ref name="sun-fujita-2010" >PMID: 20430973</ref>. <scene name='Metal-Ligand_Polyhedra/Polyhedron_main_chains/10'>24 palladium ions</scene> form the vertices of a 26-face polyhedron<ref>M24L48 forms a 26-faced ''rhombicubooctahedron'' with 18 square faces and 8 triangular faces. In this instance, the rectangular faces are very close to squares 13.35 Ångstroms on a side.</ref>. Three square faces and one triangular face meet at each vertex. | ||
Each palladium ion is coordinated by <scene name='Metal-Ligand_Polyhedra/Polyhedron_main_chains/9'>four nitrogens</scene>. The nitrogens are bridged by a <scene name='Metal-Ligand_Polyhedra/Single_main_chain_ligand/ | Each palladium ion is coordinated by <scene name='Metal-Ligand_Polyhedra/Polyhedron_main_chains/9'>four nitrogens</scene>. The nitrogens are bridged by a <scene name='Metal-Ligand_Polyhedra/Single_main_chain_ligand/2'>dipyridylthiophene</scene> ("ligand"). There are two ligand molecules (L) per metal ion (M); hence, this structure is called '''M24L48'''. | ||
The models shown thus far are simplified, including only the "main chain". The actual M24L48 complex analyzed crystallographically contained a substituent of -OCH<sub>2</sub>CH<sub>2</sub>O- on each thiophene ring, PF<sub>6</sub><sup>-</sup> counterions bound to the surface of the polyhedron, and hydrogen atoms. Here is the <scene name='Metal-Ligand_Polyhedra/M2l1_with_och2ch2o_h_pf6/ | The models shown thus far are simplified, including only the "main chain". The actual M24L48 complex analyzed crystallographically contained a substituent of -OCH<sub>2</sub>CH<sub>2</sub>O- on each thiophene ring, PF<sub>6</sub><sup>-</sup> counterions bound to the surface of the polyhedron, and hydrogen atoms. Here is the <scene name='Metal-Ligand_Polyhedra/M2l1_with_och2ch2o_h_pf6/2'>chemically complete M2L1 subunit</scene> (but lacking the three additional nitrogens coordinating each palladium, and water, which was not resolved crystallographically). Here is the <scene name='Metal-Ligand_Polyhedra/Full_polyhedron/2'>complete M24L48 polyhedron</scene> (but lacking PF<sub>6</sub> and water). | ||
The diameter of this M24L48 polyhedron is 40 Å (Pd to farthest Pd). A sphere of 50 Å circumscribes the molecular shell, and a sphere of 36 Å can be inscribed in the interior. In comparison, the diameter of the M12L24 polyhedron (see below) is 26 Å (Pd to farthest Pd). | The diameter of this M24L48 polyhedron is 40 Å (Pd to farthest Pd). A sphere of 50 Å circumscribes the molecular shell, and a sphere of 36 Å can be inscribed in the interior. In comparison, the diameter of the M12L24 polyhedron (see below) is 26 Å (Pd to farthest Pd). | ||