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Shape and Symmetry of Heptacoordinate Transition‐Metal Complexes: Structural Trends
Author(s) -
Casanova David,
Alemany Pere,
Bofill Josep M.,
Alvarez Santiago
Publication year - 2003
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200390145
Subject(s) - pentagonal bipyramidal molecular geometry , polyhedron , trigonal bipyramidal molecular geometry , bipyramid , icosahedral symmetry , crystallography , octahedron , symmetry (geometry) , transition metal , chemistry , octahedral symmetry , phosphine , chemical physics , computational chemistry , materials science , geometry , crystal structure , mathematics , catalysis , ion , biochemistry , organic chemistry
The stereochemistries of heptacoordinate transition‐metal complexes are analyzed by using continuous symmetry and shape measures of their coordination spheres. The distribution of heptacoordination through the transition‐metal series is presented based on structural database searches including organometallic and Werner‐type molecular complexes, metalloproteins, and extended solids. The most common polyhedron seems to be the pentagonal bipyramid, while different preferences are found for specific families of compounds, as in the complexes with three or four carbonyl or phosphine ligands, which prefer the capped octahedron or the capped trigonal prism rather than the pentagonal bipyramid. The symmetry maps for heptacoordination are presented and shown to be helpful for detecting stereochemical trends. The maximal symmetry interconversion pathways between the three most common polyhedra are defined in terms of symmetry constants and a large number of experimental structures are seen to fall along those paths.