Chemistry and Spectroscopy of the Transition Metals Structure of metal complexes ● Oxidation states of metals Color/Speetroscopy ·Magnetic Properties Chelate Effects Electron Transfer Chemistry XV-1
Chemistry and Spectroscopy of the Transition Metals • Structure of metal complexes • Oxidation states of metals • Color/Spectroscopy • Magnetic Properties • Chelate Effects • Electron Transfer Chemistry XV-1
Nobel Prize in Chemistry,1913 Alfred Werner "in recognition of his work on the linkage of atoms in molecules by which he has thrown new light on earlier investigations and opened up new fields of research especially in inorganic chemistry' Zurich University XV-2
Alfred Werner Nobel Prize in Chemistry, 1913 "in recognition of his work on the linkage of atoms in molecules by which he has thrown new light on earlier investigations and opened up new fields of research especially in inorganic chemistry” Zurich University XV-2
Stereochemistry of Coordination Complexes Pt (NH3)2Cl2 NH3 NH3 CI Pt Pt CI NH CI NH3 Orange-Yellow Pale Yellow (dipole moment) No dipole (cis-platin) XV-3
Pt (NH3)2Cl2 Stereochemistry of Coordination Complexes Pt Cl Cl NH3 NH3 Pt NH3 Cl NH3 Cl Orange-Yellow (dipole moment) (cis-platin) Pale Yellow No dipole XV-3
Tetrahedral MA2B2 ODoes MA2B2 have optical isomers? A B 59
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Square Planar Complexes [Pt(NH)2C12]exists as cis and trans isomers 45 V.5
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Chemistry of Coordination Compounds OTransition metal compounds (demo samples) Ovariable oxidation numb er ●colored ●unusual comp osition Ooften contain covalent compounds bonded to the metal ●nydrates OLewis acid-base adduct Ocoordinate covalent bonds Ounusual magnetic properties XV-6
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The Structure of Complexes OContain coordinate covalent bonds OUnusual composition:Central metal ion or atom ligands counter ion (if needed) OCalled complex ion if charged ●[Cu(NH;)a]SO4H2O hydrate anion ligands central metal ion 2 V.7
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Coordination Sphere ONature of coor dination compounds is determined by both the oxidation number of the central ion and its coor dination number. OThe coordination number is (mostly) constant for a metal with a given oxidation number. OFirst coordination sphere:central metal ion and its ligands 8 -8
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First Coordination Sphere D -NII. n- IL, A.[FE(CN] C.[PHNIIC] coolinalior NTT: coordiralinr n1 mher一f nimber-6 XII; TpnleR2 pdb /M1.3 h B.[TuNH )] coordinalioc mimher -4 Pnt.plb XV
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First Coordination Sphere OCoordination number is often 2 x oxidation number (many exceptions) OMostly predictable geometry: OCoordination number =2,linear OCoordination number 4,square planar or tetrahedral OCoordination number 6,octahedral 10 10
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