1 / 11

Isomerism & Crystal Field Theory Chapter 24 – Lecture 3

Isomerism & Crystal Field Theory Chapter 24 – Lecture 3. Chemistry 123 Spring 2008 Dr. Woodward. Isomers. Different ligands make bonds to the metal. Ligands bond to the metal through different atoms. Ligands have different (ligand) neighbors. Molecules are non-superimposable mirror images.

reuben-reilly
Download Presentation

Isomerism & Crystal Field Theory Chapter 24 – Lecture 3

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Isomerism & Crystal Field TheoryChapter 24 – Lecture 3 Chemistry 123 Spring 2008 Dr. Woodward

  2. Isomers Different ligands make bonds to the metal Ligands bond to the metal through different atoms Ligands have different (ligand) neighbors Molecules are non-superimposable mirror images

  3. Linkage Isomers

  4. Geometric Isomers

  5. Optical Isomers

  6. Intra-atomic (d to d) excitations MnSO4 FeSO4 CoSO4 NiSO4 CuSO4 ZnSO4 In these complexes the color comes from absorption of light that leads to excitation of an electron from one d-orbital to a different d-orbital on the same metal cation.

  7. [M(H2O)6]n+ Complex ions M MO6 Octahedron H2O

  8. Crystal Field Splitting (Octahedron) Energy • dz2 & dx2-y2 orbitals (eg) • Point directly at the ligands • Stronger (repulsive) interaction with the ligands dx2-y2 dz2 • dxy, dyz & dxz orbitals (t2g) • Point between the ligands • Weaker (repulsive) interaction with the ligands dxy dyz dxz Electrons in d-orbitals are repelled from the electrons in the ligands. The repulsion is stronger for electrons in d-orbitals pointing directly at the ligands.

  9. D Energy Levels of d-orbitals in an octahedron Energy dz2 dx2-y2 dz2 dxz dxy dyz dx2-y2 Cr3+ ion with a spherical crystal field dxy dyz dxz dz2 dxz dyz dx2-y2 Cr3+ ion in an octahedral crystal field dxy Free Cr3+ ion

  10. light (photon) Electronic Excitation dx2-y2 dz2 Energy dx2-y2 dz2 eg D = Crystal Field Splitting Energy t2g dxy dyz dxz dxy dyz dxz

  11. [Cr3+(H2O)6]3+ Absorption Spectra Antibonding (s*) Metal-Ligand MO’s Doct Nonbonding Metal d MO’s

More Related