TD-DFT excitation energies of neutral molecules

From NWChem

Viewed 88 times, With a total of 0 Posts
Jump to: navigation, search

Just Got Here
Threads 2
Posts 3
Dear all,

I have been trying to calculate the excitation energies of small polyaromatic hydrocarbon molecules like naphthalene, pyrene etc using the Tamm-Dancoff approximation via the TD-DFT module.

My first benchmark was with the naphthalene cation, for which I managed to reproduce available TD-DFT data from the literature.

In the case of neutral molecules, all of my attempts failed to compare with any literature data.

My calculation steps are the following:
1. Optimize the geometry of the neutral molecule with tight convergence criteria using odft and mult=1.
2. Retrieve the final geometry and movecs file and use them in a TD-DFT calculation.

This is an example input script:

echo
start  pyr_tddft-tda_b3lyp_6-31+gs_spin_1_sym
title "pyr_tddft-tda_b3lyp_6-31+gs_spin_1_sym"
charge 0
geometry noautoz nocenter
 load preview_pyr_b3lyp_6-31+gs_spin_1_sym-008.xyz
end
basis
 * library "6-31+g*"
end
dft
 direct
 vectors input pyr_b3lyp_6-31+gs_spin_1_sym.movecs output tddft.movecs
 xc b3lyp
 grid fine
 odft
 mult 1
end
tddft
 cis
 nroots 20
end
task tddft energy


According to https://doi.org/10.1016/S0166-1280(02)00787-X, I should get
b2u	3.66
b1u	3.73
b3g	4.29	Forbidden
b3g	4.57	Forbidden
b2u	4.59


What NWCHEM 6.5 gives me is the following:

Ground state ag       -615.792027823211 a.u.
  <S2> =  -0.0000

  ----------------------------------------------------------------------------
  Root   1         b2u            0.087699603 a.u.                2.3864 eV 
  <S2> =   2.0000
  ----------------------------------------------------------------------------
     Transition Moments    X -0.00000   Y -0.00000   Z -0.00000
     Transition Moments   XX  0.00000  XY -0.00000  XZ  0.00000
     Transition Moments   YY -0.00000  YZ  0.00000  ZZ  0.00000
     Dipole Oscillator Strength                         0.00000

     Occ.   50 alpha au  ---  Virt.   57 alpha b2g   -0.07693
     Occ.   51 alpha b1u ---  Virt.   56 alpha b3g    0.08126
     Occ.   52 alpha b3g ---  Virt.   55 alpha b1u    0.07214
     Occ.   53 alpha b2g ---  Virt.   54 alpha au    -0.68843
     Occ.   50 beta  au  ---  Virt.   57 beta  b2g    0.07693
     Occ.   51 beta  b1u ---  Virt.   56 beta  b3g   -0.08126
     Occ.   52 beta  b3g ---  Virt.   55 beta  b1u   -0.07214
     Occ.   53 beta  b2g ---  Virt.   54 beta  au     0.68843
  ----------------------------------------------------------------------------
  Root   2         b3u            0.126585552 a.u.                3.4446 eV 
  <S2> =   2.0000
  ----------------------------------------------------------------------------
     Transition Moments    X  0.00000   Y -0.00000   Z -0.00000
     Transition Moments   XX  0.00000  XY -0.00000  XZ  0.00000
     Transition Moments   YY -0.00000  YZ  0.00000  ZZ -0.00000
     Dipole Oscillator Strength                         0.00000

     Occ.   52 alpha b3g ---  Virt.   54 alpha au    -0.41733
     Occ.   53 alpha b2g ---  Virt.   55 alpha b1u    0.56371
     Occ.   52 beta  b3g ---  Virt.   54 beta  au     0.41733
     Occ.   53 beta  b2g ---  Virt.   55 beta  b1u   -0.56371
  ----------------------------------------------------------------------------
  Root   3         b3u            0.132444477 a.u.                3.6040 eV 
  <S2> =   2.0000
  ----------------------------------------------------------------------------
     Transition Moments    X  0.00000   Y  0.00000   Z -0.00000
     Transition Moments   XX  0.00000  XY  0.00000  XZ  0.00000
     Transition Moments   YY -0.00000  YZ  0.00000  ZZ -0.00000
     Dipole Oscillator Strength                         0.00000

     Occ.   52 alpha b3g ---  Virt.   54 alpha au     0.56526
     Occ.   53 alpha b2g ---  Virt.   55 alpha b1u    0.41969
     Occ.   52 beta  b3g ---  Virt.   54 beta  au    -0.56526
     Occ.   53 beta  b2g ---  Virt.   55 beta  b1u   -0.41969
  ----------------------------------------------------------------------------
  Root   4         b1g            0.134861874 a.u.                3.6698 eV 
  <S2> =   2.0000
  ----------------------------------------------------------------------------
     Transition Moments    X -0.00000   Y  0.00000   Z -0.00000
     Transition Moments   XX  0.00000  XY -0.00000  XZ  0.00000
     Transition Moments   YY -0.00000  YZ -0.00000  ZZ -0.00000
     Dipole Oscillator Strength                         0.00000

     Occ.   46 alpha b2g ---  Virt.   56 alpha b3g    0.08504
     Occ.   49 alpha b1u ---  Virt.   54 alpha au     0.06845
     Occ.   51 alpha b1u ---  Virt.   54 alpha au     0.41875
     Occ.   51 alpha b1u ---  Virt.   68 alpha au    -0.05867
     Occ.   53 alpha b2g ---  Virt.   56 alpha b3g   -0.53956
     Occ.   53 alpha b2g ---  Virt.   63 alpha b3g   -0.05984
     Occ.   46 beta  b2g ---  Virt.   56 beta  b3g   -0.08504
     Occ.   49 beta  b1u ---  Virt.   54 beta  au    -0.06845
     Occ.   51 beta  b1u ---  Virt.   54 beta  au    -0.41875
     Occ.   51 beta  b1u ---  Virt.   68 beta  au     0.05867
     Occ.   53 beta  b2g ---  Virt.   56 beta  b3g    0.53956
     Occ.   53 beta  b2g ---  Virt.   63 beta  b3g    0.05984
  ----------------------------------------------------------------------------
  Root   5         b3u            0.137760609 a.u.                3.7487 eV 
  <S2> =   0.0000
  ----------------------------------------------------------------------------
     Transition Moments    X  0.05596   Y  0.00000   Z  0.00000
     Transition Moments   XX  0.00000  XY  0.00000  XZ -0.00000
     Transition Moments   YY  0.00000  YZ -0.00000  ZZ -0.00000
     Dipole Oscillator Strength                         0.00029

     Occ.   52 alpha b3g ---  Virt.   54 alpha au     0.47892
     Occ.   53 alpha b2g ---  Virt.   55 alpha b1u    0.51818
     Occ.   52 beta  b3g ---  Virt.   54 beta  au     0.47892
     Occ.   53 beta  b2g ---  Virt.   55 beta  b1u    0.51818
  ----------------------------------------------------------------------------
  Root   6         b2u            0.141722835 a.u.                3.8565 eV 
  <S2> =   0.0000
  ----------------------------------------------------------------------------
     Transition Moments    X  0.00000   Y -1.85003   Z -0.00000
     Transition Moments   XX  0.00000  XY  0.00000  XZ -0.00000
     Transition Moments   YY -0.00000  YZ -0.00000  ZZ -0.00000
     Dipole Oscillator Strength                         0.32337

     Occ.   51 alpha b1u ---  Virt.   56 alpha b3g   -0.09828
     Occ.   52 alpha b3g ---  Virt.   55 alpha b1u    0.27567
     Occ.   53 alpha b2g ---  Virt.   54 alpha au    -0.63499
     Occ.   51 beta  b1u ---  Virt.   56 beta  b3g   -0.09828
     Occ.   52 beta  b3g ---  Virt.   55 beta  b1u    0.27567
     Occ.   53 beta  b2g ---  Virt.   54 beta  au    -0.63499
  ----------------------------------------------------------------------------
  Root   7         ag             0.147505603 a.u.                4.0138 eV 
  <S2> =   2.0000
  ----------------------------------------------------------------------------
     Transition Moments    X -0.00000   Y  0.00000   Z  0.00000
     Transition Moments   XX -0.00000  XY -0.00000  XZ -0.00000
     Transition Moments   YY  0.00000  YZ  0.00000  ZZ  0.00000
     Dipole Oscillator Strength                         0.00000

     Occ.   49 alpha b1u ---  Virt.   55 alpha b1u    0.06661
     Occ.   50 alpha au  ---  Virt.   54 alpha au     0.45020
     Occ.   51 alpha b1u ---  Virt.   55 alpha b1u   -0.10890
     Occ.   52 alpha b3g ---  Virt.   56 alpha b3g   -0.12598
     Occ.   52 alpha b3g ---  Virt.   63 alpha b3g    0.05204
     Occ.   53 alpha b2g ---  Virt.   57 alpha b2g    0.49427
     Occ.   53 alpha b2g ---  Virt.   71 alpha b2g   -0.07603
     Occ.   49 beta  b1u ---  Virt.   55 beta  b1u   -0.06661
     Occ.   50 beta  au  ---  Virt.   54 beta  au    -0.45020
     Occ.   51 beta  b1u ---  Virt.   55 beta  b1u    0.10890
     Occ.   52 beta  b3g ---  Virt.   56 beta  b3g    0.12598
     Occ.   52 beta  b3g ---  Virt.   63 beta  b3g   -0.05204
     Occ.   53 beta  b2g ---  Virt.   57 beta  b2g   -0.49427
     Occ.   53 beta  b2g ---  Virt.   71 beta  b2g    0.07603
  ----------------------------------------------------------------------------
  Root   8         b2u            0.147646939 a.u.                4.0177 eV 
  <S2> =   2.0000
  ----------------------------------------------------------------------------
     Transition Moments    X -0.00000   Y  0.00000   Z -0.00000
     Transition Moments   XX -0.00000  XY  0.00000  XZ  0.00000
     Transition Moments   YY  0.00000  YZ -0.00000  ZZ -0.00000
     Dipole Oscillator Strength                         0.00000

     Occ.   49 alpha b1u ---  Virt.   56 alpha b3g    0.05034
     Occ.   49 alpha b1u ---  Virt.   63 alpha b3g   -0.09058
     Occ.   50 alpha au  ---  Virt.   57 alpha b2g    0.05667
     Occ.   51 alpha b1u ---  Virt.   56 alpha b3g   -0.10367
     Occ.   52 alpha b3g ---  Virt.   55 alpha b1u   -0.67659
     Occ.   53 alpha b2g ---  Virt.   54 alpha au    -0.09841
     Occ.   49 beta  b1u ---  Virt.   56 beta  b3g   -0.05034
     Occ.   49 beta  b1u ---  Virt.   63 beta  b3g    0.09058
     Occ.   50 beta  au  ---  Virt.   57 beta  b2g   -0.05667
     Occ.   51 beta  b1u ---  Virt.   56 beta  b3g    0.10367
     Occ.   52 beta  b3g ---  Virt.   55 beta  b1u    0.67659
     Occ.   53 beta  b2g ---  Virt.   54 beta  au     0.09841
  ----------------------------------------------------------------------------
  Root   9         b1g            0.158505126 a.u.                4.3131 eV 
  <S2> =   0.0000
  ----------------------------------------------------------------------------
     Transition Moments    X  0.00000   Y  0.00000   Z -0.00000
     Transition Moments   XX -0.00000  XY  0.08330  XZ  0.00000
     Transition Moments   YY  0.00000  YZ -0.00000  ZZ  0.00000
     Dipole Oscillator Strength                         0.00000

     Occ.   51 alpha b1u ---  Virt.   54 alpha au     0.21703
     Occ.   53 alpha b2g ---  Virt.   56 alpha b3g    0.67023
     Occ.   51 beta  b1u ---  Virt.   54 beta  au     0.21703
     Occ.   53 beta  b2g ---  Virt.   56 beta  b3g    0.67023
  ----------------------------------------------------------------------------
  Root  10         b1g            0.160090362 a.u.                4.3563 eV 
  <S2> =   2.0000
  ----------------------------------------------------------------------------
     Transition Moments    X -0.00000   Y -0.00000   Z -0.00000
     Transition Moments   XX  0.00000  XY  0.00000  XZ  0.00000
     Transition Moments   YY -0.00000  YZ  0.00000  ZZ -0.00000
     Dipole Oscillator Strength                         0.00000

     Occ.   51 alpha b1u ---  Virt.   54 alpha au    -0.54604
     Occ.   53 alpha b2g ---  Virt.   56 alpha b3g   -0.43893
     Occ.   53 alpha b2g ---  Virt.   63 alpha b3g    0.06401
     Occ.   51 beta  b1u ---  Virt.   54 beta  au     0.54604
     Occ.   53 beta  b2g ---  Virt.   56 beta  b3g    0.43893
     Occ.   53 beta  b2g ---  Virt.   63 beta  b3g   -0.06401


There seems to be something wrong with the way I am telling NWCHEM to execute my calculations...

I appreciate any input!!

Best regards,
Orestis


Forum >> NWChem's corner >> General Topics



Who's here now Members 0 Guests 0 Bots/Crawler 1


AWC's: 2.5.10 MediaWiki - Stand Alone Forum Extension
Forum theme style by: AWC