Différences entre les versions de « VBTutorial4 »

De Workshops
Aller à la navigation Aller à la recherche
Ligne 88 : Ligne 88 :
  
 
In HL-CI we define an effective CI hamiltonian that concerns the interaction between  the (localized) Lewis structures <math> \Psi_{I}</math> and <math> \Psi_{II}</math>: <math> \Psi_{HL-CI}=c_{I}\Psi_{I}+c_{II}\Psi_{II}</math>. This CI must give the Huckel energy of the delocalized wave function. <math> E_{HL-CI}=E_{Huckel}</math>
 
In HL-CI we define an effective CI hamiltonian that concerns the interaction between  the (localized) Lewis structures <math> \Psi_{I}</math> and <math> \Psi_{II}</math>: <math> \Psi_{HL-CI}=c_{I}\Psi_{I}+c_{II}\Psi_{II}</math>. This CI must give the Huckel energy of the delocalized wave function. <math> E_{HL-CI}=E_{Huckel}</math>
 +
 +
*1/ Write the expression of the CI secular determinant that has the energy ot the delocalized wave function, and show that the off-diagonal term is <math>H_{I-II}=0.71\beta</math>. (in HL-CI the off diagonal term is supposed <0).
 +
 +
*2/ Resolve the secular equations of the CI and find that
 +
<math> \Psi_{HL-CI}=0.81\Psi_{I}+0.58\Psi_{II}</math>, hence the weights of the structures (I/II)=(66%/34%)
 +
 +
Note that in HL-CI <math><Psi_{I}|\Psi_{II}>=0</math>
 
  {| class="collapsible collapsed wikitable"
 
  {| class="collapsible collapsed wikitable"
 
|-
 
|-
!<big>'''answer'''</big>
+
!<big>'''help'''</big>
 
|-
 
|-
 
|
 
|
Ligne 101 : Ligne 108 :
 
These values are used as  <math>H_{I-I}</math> and <math>H_{II-II}</math> for the CI matrix.  
 
These values are used as  <math>H_{I-I}</math> and <math>H_{II-II}</math> for the CI matrix.  
 
  |}
 
  |}
*1/ Write the expression of the CI secular determinant that has the energy ot the delocalized wave function, and show that the off-diagonal term is <math>H_{I-II}=0.71\beta</math>. (in HL-CI the off diagonal term is supposed <0).
 
 
*2/ Resolve the secular equations of the CI and find that
 
<math> \Psi_{HL-CI}=0.81\Psi_{I}+0.58\Psi_{II}</math>, hence the weights of the structures (I/II)=(66%/34%)
 
 
Note that in HL-CI <math><Psi_{I}|\Psi_{II}>=0</math>
 
  
 
====Allyl Radical with HLP====
 
====Allyl Radical with HLP====

Version du 29 juin 2012 à 13:30

<< Return to the program


How to modify this page :

  • first : log in (top right of this page) ;
  • click on [edit] (far right) to edit a section of the page ;
  • write your text directly in the wiki page, and click on the "Save page" button (bottom left) to save your modifications

Pictures : how to insert a picture in your text

See also this page for an introduction to the basics of the wiki syntax


BLW method & HuLiS program