Performance of dft sergio aragon san francisco state university caltech pasi january 4 16 2004 l.jpg
Sponsored Links
This presentation is the property of its rightful owner.
1 / 17

Performance of DFT Sergio Aragon San Francisco State University CalTech PASI January 4-16, 2004 PowerPoint PPT Presentation


  • 92 Views
  • Uploaded on
  • Presentation posted in: General

Performance of DFT Sergio Aragon San Francisco State University CalTech PASI January 4-16, 2004. H 2 Dissociation Curve. Performance: Ozone. Bond lengths & Bond Angles. Koch & Holthausen. Octahedral Cr Complex. Octahedral Metallic Carbonyls. Vibrational Frequencies. Thermochemistry.

Download Presentation

Performance of DFT Sergio Aragon San Francisco State University CalTech PASI January 4-16, 2004

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


Performance of DFT Sergio AragonSan Francisco State UniversityCalTech PASI January 4-16, 2004


H2 Dissociation Curve


Performance: Ozone


Bond lengths & Bond Angles

Koch &

Holthausen


Octahedral Cr Complex


Octahedral Metallic Carbonyls


Vibrational Frequencies


Thermochemistry


Ionization Energies

HF under-estimates ionization energies: more correlation in the neutral than in the ion.


Electron Affinities

Affinities are very problematic for HF//anything methods. Extra electron adds correlation and is very diffuse.

DFT does reasonably well.


Excitation Energies: Ethylene

Poor asymptotic behavior of ordinary functionals yields a deteriorating picture as the excitation energy increases.

Asymptotically corrected functionals such as PBE perform as well as the very expensive CAS methods.


Dipole Moments

HF predicts the wrong sign of the dipole moment for CO!

DFT performs very well.


Polarizabilities

Polarizabilities are inversely proportional to orbital energy differences. DFT, with poor asymptotics, has high values of the HOMO energy and overestimates the polarizability.


Hydrogen bonding: Water Dimer

The fabulous numbers for the BLYP functional have been shown to be due to fortuitous error cancellation. Hybrid functionals do not overperform the HF//MP2 level.


Further Study

Koch, W. and Holthausen, M.C., “A Chemist’s Guide to Density Functional Theory”, Wiley-VCH: New York, 2000.

Further comparisons are available on:

IR intensities

NMR chemical shifts and spin-spin couplings

Hyperpolarizabilities

ESR tensors & Hyperfine couplings

Weakly bound systems & clusters.


Atoms in Molecules


  • Login