Transition Metal Chemistry and Coordination CompoundsSlide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31Slide 32Transition Metal Chemistry and Coordination CompoundsChapter 22Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.22.1The Transition Metals22.122.1Oxidation States of the 1st Row Transition Metals(most stable oxidation numbers are shown in red)22.122.1Ionization Energies for the 1st Row Transition MetalsScandium Titanium VanadiumChromium Manganese IronCobalt Nickel Copper22.2Coordination CompoundsA coordination compound typically consists of a complex ion and a counter ion.A complex ion contains a central metal cation bonded to one or more molecules or ions.The molecules or ions that surround the metal in a complex ion are called ligands.A ligand has at least one unshared pair of valence electronsHOH••••••HNHH••••Cl••••-••CO••22.3Coordination Compounds22.3The atom in a ligand that is bound directly to the metal atom is the donor atom.HOH••••••HNHHThe number of donor atoms surrounding the central metal atom in a complex ion is the coordination number.Ligands with:one donor atommonodentatetwo donor atomsbidentatethree or more donor atomspolydentateH2O, NH3, Cl-ethylenediamineEDTACoordination Compounds22.3H2N CH2 CH2 NH2••••bidentate ligandpolydentate ligand(EDTA)Bidentate and polydentate ligands are called chelating agents22.3EDTA Complex of Lead22.3What are the oxidation numbers of the metals in K[Au(OH)4] and [Cr(NH3)6](NO3)3 ?OH- has charge of -1K+ has charge of +1? Au + 1 + 4x(-1) = 0Au = +3NO3- has charge of -1NH3 has no charge? Cr + 6x(0) + 3x(-1) = 0Cr = +322.3Naming Coordination Compounds22.3•The cation is named before the anion.•Within a complex ion, the ligands are named first in alphabetical order and the metal atom is named last.•The names of anionic ligands end with the letter o. Neutral ligands are usually called by the name of the molecule. The exceptions are H2O (aquo), CO (carbonyl), and NH3 (ammine).•When several ligands of a particular kind are present, the Greek prefixes di-, tri-, tetra-, penta-, and hexa- are used to indicate the number. If the ligand contains a Greek prefix, use the prefixes bis, tris, and tetrakis to indicate the number.•The oxidation number of the metal is written in Roman numerals following the name of the metal.•If the complex is an anion, its name ends in –ate.22.322.3What is the systematic name of [Cr(H2O)4Cl2]Cl ?tetraaquodichlorochromium(III) chlorideWrite the formula of tris(ethylenediamine)cobalt(II) sulfate[Co(en)3]SO4Structure of Coordination Compounds22.4Coordination number Structure246LinearTetrahedral or Square planarOctahedralStructure of Coordination Compounds22.4Stereoisomers are compounds that are made up of the same types and numbers of atoms bonded together in the same sequence but with different spatial arrangements.Geometric isomers are stereoisomers that cannot be interconverted without breaking a chemical bond.cis-[Pt(NH3)2Cl2]trans-[Pt(NH3)2Cl2]Structure of Coordination Compounds22.4cis-[Co(NH3)4Cl2] trans-[Co(NH3)4Cl2]Are these additional geometric isomers of [Co(NH3)4Cl2]?cistransStructure of Coordination Compounds22.4Optical isomers are nonsuperimposable mirror images.cis-[Co(en)2Cl2] trans-[Co(en)2Cl2]optical isomerschiralnot optical isomersachiralStructure of Coordination Compounds22.4Chiral molecules are optically active.Bonding in Coordination Compounds22.5All equal in energy in the absence of ligands!Bonding in Coordination Compounds22.5Isolatedtransition metalatomBondedtransition metalatom Crystal field splitting ( ) is the energy difference between two sets of d orbitals in a metal atom when ligands are presentBonding in Coordination Compounds22.5E = hThe absorption maximum for the complex ion [Co(NH3)6]3+ occurs at 470 nm. What is the color of the complex and what is the crystal field splitting in kJ/mol?Absorbs blue, will appear orange. = hhc=(6.63 x 10-34 J s) x (3.00 x 108 m s-1)470 x 10-9 m= = 4.23 x 10-19 J (kJ/mol) = 4.23 x 10-19 J/atom x 6.022 x 1023 atoms/mol= 255 kJ/mol22.5Bonding in Coordination Compounds22.5I- < Br- < Cl- < OH- < F- < H2O < NH3 < en < CN- < COSpectrochemical SeriesStrong field ligandsLarge Weak field ligandsSmall Bonding in Coordination Compounds22.522.5Orbital Diagrams for High Spin and Low Spin Octahedral ComplexesBonding in Coordination Compounds22.5Bonding in Coordination Compounds22.5Chemistry In Action: Coordination Compounds in Living SystemsChemistry In Action: Cisplatin – The Anticancer