an introduction to the chemistry of chromium l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
An Introduction to the Chemistry of Chromium PowerPoint Presentation
Download Presentation
An Introduction to the Chemistry of Chromium

Loading in 2 Seconds...

play fullscreen
1 / 19

An Introduction to the Chemistry of Chromium - PowerPoint PPT Presentation


  • 225 Views
  • Uploaded on

An Introduction to the Chemistry of Chromium. Ethan Englund Augustana College 05.10.02. Chromium Chemistry. Chromium - Comes form the Greek word “chroma” meaning colored. First Identified in the PbCrO 4 Multiple Oxidation States . Cr(Acac) 3. Full Name is Chromium Acetylacetonate

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

An Introduction to the Chemistry of Chromium


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
an introduction to the chemistry of chromium

An Introduction to the Chemistry of Chromium

Ethan Englund

Augustana College

05.10.02

chromium chemistry
Chromium Chemistry
  • Chromium - Comes form the Greek word “chroma” meaning colored.
  • First Identified in the PbCrO4
  • Multiple Oxidation States
cr acac 3
Cr(Acac)3
  • Full Name is Chromium Acetylacetonate
  • Octahedral Complex of Cr III
  • Optically Active
chromium acac synthesis
Chromium Acac Synthesis
  • Acetylacetone is added to a solution containing Cr (III) ions and urea.
  • The solution is heated thoroughly for around 1 ~ 2 hours.
  • Yields a deep red solution with dark red precipitate.
chromium d orbital split
Chromium d Orbital Split
  • Cr (III) - Typical d3 octahedral metal ion.
  • Ligand Field Strength Unimportant
visible spectrum
Visible Spectrum
  • Obvious Color
  • D  D Transitions
  • From this, the LFSE (o) and B can be determined.
interpreting spectrum data tunabe sugano diagram
Interpreting Spectrum Data: Tunabe - Sugano Diagram
  • From this, one can determine the Racah parameter.
  • Also can give the Octahedral Splitting Energy
symmetry and optical activity
Symmetry and Optical Activity
  • D3 Symmetry
  • Optical activity possible because of the enantiomers.
  • Right Hand Screw Vs. Left Hand Screw Formation
the joys of computational chem
The Joys of Computational Chem
  • Above: The Elctrostatic Potential Graphed on the Electron Density via ZINDO on CAChe
singly and doubly occupied orbitals
Singly and Doubly Occupied Orbitals

Prediction based on Jaguar: B88 LYP

Some Oddities in the Predictions

t 2g vs e g orbitals
T2g Vs. eg Orbitals
  • Seem to show dx2-y2 orbitals
  • Along with dz2 indicate eg
chromium acetate
Chromium Acetate
  • Bidentate Acetate Ligands
  • Metal-Metal Bond
  • Computational methods and approaches
the formation of a delta bond in a cr ii complex
The Formation of a Delta Bond in a Cr(II) Complex
  • Commonly referred to as a quadruple bond.
  • Has 8 available valence electrons
  • Bond Order of 4
orbital view of the quadruple bond
Orbital View of the Quadruple Bond
  • The d orbitals of the delta bond
  • dx2-y2 orbitals occupied M-L bonds
conclusion
Conclusion
  • Transition Metal Computational Work Continues to Gain Interest
  • The Chromium Chemistry described shows a lot of generalities in transition metal chemistry
bibliography
Bibliography
  • Atkins, Shriver. Inorganic Chemistry: Third Edition. Freeman and Company N.Y. 1999
  • Gray, Swanson, Crawford. Project ACAC: An Experimental Investigation In Synthesis and Structure. Bogden and Quigley Inc. Belmont, Ca. 1972
appreciation goes out to
Appreciation goes out to…
  • Dr. Viste for his invaluable Quantum/Computational advise
  • Dr. Lindbeck for her guidance in advanced inorganic chemistry
  • Augustana College