Application of Gradient-Corrected Density Functional Theory to the Structures and Thermochemistries of $\mbox{ScF}_3$, $\mbox{TiF}_4$, $\mbox{VF}_5$, and $\mbox{CrF}_6$

Physics – Chemical Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

18 pages, latex, 1 figure, Submitted to Journal of Chemical Physics

Scientific paper

10.1063/1.469000

Density functional theory(DFT) and Hartree-Fock(HF) calculations are reported for the family of transition metal fluorides $\mbox{ScF}_3$, $\mbox{TiF}_4$, $\mbox{VF}_5$, and $\mbox{CrF}_6$. Both HF and the local-density-aproximation (LDA) yield excellent agreement with experimental bond lengths, while the B-LYP gradient-corrected density functional gives bond lengths $0.04-0.05$ \AA\ too long. An investigation of various combinations of exchange and correlation functionals shows that, for this series, the origin of this behavior lies in the Becke exchange functional. Much improved bond distances are found using the hybrid HF/DFT functional advocated by Becke. This approximation also leads to much improved thermochemistries. The LDA overestimates average bond energies in this series by $30-40$ kcal/mol, whereas the B-LYP functional overbinds by only $\sim8-12$ kcal/mol, and the hybrid HF/DFT method overbinds by only $\sim 2$ kcal/mol. The hybrid method predicts the octahedral isomer of $\mbox{CrF}_6$ to be more stable than the trigonal prismatic form by $14$ kcal/mol. Comparison of theoretical vibrational frequencies with experiment supports the assignment of an octahedral geometry.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Application of Gradient-Corrected Density Functional Theory to the Structures and Thermochemistries of $\mbox{ScF}_3$, $\mbox{TiF}_4$, $\mbox{VF}_5$, and $\mbox{CrF}_6$ does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Application of Gradient-Corrected Density Functional Theory to the Structures and Thermochemistries of $\mbox{ScF}_3$, $\mbox{TiF}_4$, $\mbox{VF}_5$, and $\mbox{CrF}_6$, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Application of Gradient-Corrected Density Functional Theory to the Structures and Thermochemistries of $\mbox{ScF}_3$, $\mbox{TiF}_4$, $\mbox{VF}_5$, and $\mbox{CrF}_6$ will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-464482

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.