Clicker Question22: Coordination ChemistryCoordination Compounds & LifeCoordination Compounds & LifeFinding the Metal d-electron countCrystal Field TheoryCrystal Field TheoryCrystal Field TheoryOctahedral Crystal FieldOctahedral Electron ConfigurationsOctahedral Electron ConfigurationsOctahedral Electron ConfigurationsOctahedral Electron ConfigurationsSquare Planar Crystal FieldSquare Planar Crystal FieldSquare Planar Crystal FieldTetrahedral Crystal FieldTetrahedral Crystal FieldTetrahedral Crystal FieldTetrahedral Crystal FieldClicker QuestionWhich is not possible?1. Linkage isomerism in tetrahedral coordination compounds2. Linkage isomerism in octahedral coordination compounds3. Geometrical isomerism in octahedral coordination compounds4. Optical isomerism in square planar coordination compounds5. Optical isomerism in octahedral coordination compounds22: Coordination Chemistry22.1 Properties of the Transition Elements 22.2 Iron and Steel: The Use of Pyrometallurgy22.3 Copper: A Coinage Metal22.4 Silver and Gold: The Other Coinage Metals22.5 Chromium22.6 Coordinate Covalent Bonds22.7 Crystal-Field TheoryWednesday, November 12, 2014Read: Section 22.7 for Wednesday Sections 22.7 for FridayEnd of Chapter 22 Problems: 8, 14, 16, 18, 20, 21, 22, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 63, 65, 67, 73, 75, 77, 78, 79, 83, 85, 91Wednesday, November 12, 2014Read: Section 22.7 for Wednesday Sections 22.7 for FridayEnd of Chapter 22 Problems: 8, 14, 16, 18, 20, 21, 22, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 63, 65, 67, 73, 75, 77, 78, 79, 83, 85, 91Coordination Compounds & LifeHeme carries Fe2+ in myoglobin and hemoglobin*1 heme/myoglobin and 4 hemes/hemoglobin.2+Coordination Compounds & LifeVitamin B12:6-coord. Co ion bound to a heme ligandOnly known dietary use of cobalt, but it is absolutely essentialFinding the Metal d-electron countTake into account the charges of any counter ionsDetermine which ligands are neutral and which are charged (anionic) to determine ox. stated-count = valance electrons – oxidation stateNOT dependent on isomers!Crystal Field TheoryOrbital view- pay attention to axis labels!Crystal Field Theorye-pairs on the ligands create an electrostatic field.Crystal Field TheoryThis field interacts with the metal-ion d orbitals.CN-FeCN-CN-CN-CN-CN-2+3dz23dx - y2 2Along the x, y, z axes3dyz3dxy3dxzBetween axes•Ligands lie along the x, y and z axes.•The two types of d orbitals have different E in this field.In an octahedral complex:Octahedral Crystal FieldThe metal d orbitals split into two sets (e and t2):The energy gap (Δo) = octahedral crystal-field splitting energy.*Tetrahedral and square planar have different splitting patternsOctahedral Electron ConfigurationsStrong field ligands:Large ΔoLow spin complexWeak field ligands:Small ΔoHigh spin complex CN- > NO2- > en > NH3 > NCS- > H2O > F- > Cl- strong field weak fielddecreasing ΔoOctahedral Electron ConfigurationsThe size of Δo depends upon the ligands: CN- > NO2- > en > NH3 > NCS- > H2O > F- > Cl- strong field weak fieldet2et2et2d 4 varies:et2strong field ligands(large Δo)et2weak field ligands(small Δo)d 1, d 2, and d 3decreasing ΔoOctahedral Electron Configurationsd 6 configurations:et2High-spin complexsmall Δoet2Low-spin complexlarge ΔoExplain why:Hexaaquairon(II) complex is paramagneticHexacyanoiron(II) is diamagneticOctahedral Electron ConfigurationsHow many unpaired electrons are in the following octahedral ion?[Co(CN)6]3-1. 02. 23. 4Square Planar Crystal FieldHow can we form a square planar complex?As we remove the ligands on the z-axis, what happens to the energy of each d-orbital?Begin to removeligands alongz-axisOnce completelyremoved: squareplanarSquare Planar Crystal FieldThe metal d orbitals split from the octahedral diagram to form the crystal field splitting diagram for square planar:Square planar geometry is common for d8 and d9 metal complexesSquare Planar Crystal FieldHow many unpaired electrons would be in a square planar, Pt2+ metal complex?1. 02. 13. 24. 3Tetrahedral Crystal Field•Ligands lie between the x, y and z axes.In an tetrahedral complex:Tetrahedral Crystal FieldThe metal d orbitals split into two sets (e and t2):The energy gap (ΔT) = tetrahedral crystal-field splitting energy.*Notice that the energy levels are opposite of octahedral since ligands approach between the axesTetrahedral Crystal FieldOrbital filling in a tetrahedral crystal field:•ΔT is much smaller than Δo•Tetrahedral molecules are always high spind3d7d5Tetrahedral Crystal FieldHow many unpaired electrons would be in a tetrahedral, Pt2+ metal complex?1. 02. 13. 24.