X

Search Results

Searching....

7.3 Time-Dependent Density Functional Theory (TDDFT)

7.3.8 Examples

(September 1, 2024)

Example 7.22  This example shows two jobs which request variants of time-dependent density functional theory calculations. The first job, using the default value of RPA = FALSE, performs TDDFT in the Tamm-Dancoff approximation (TDA). The second job, with RPA = TRUE performs a both TDA and full TDDFT calculations.

$comment
   methyl peroxy radical
   TDDFT/TDA and full TDDFT with 6-31+G*
$end

$molecule
   0  2
   C  1.00412  -0.18045    0.00000
   O -0.24600   0.59615    0.00000
   O -1.31237  -0.23026    0.00000
   H  1.81077   0.56720    0.00000
   H  1.03665  -0.80545   -0.90480
   H  1.03665  -0.80545    0.90480
$end

$rem
   EXCHANGE          b
   CORRELATION       lyp
   CIS_N_ROOTS       5
   BASIS             6-31+G*
   SCF_CONVERGENCE   7
$end

@@@

$molecule
   read
$end

$rem
   EXCHANGE          b
   CORRELATION       lyp
   CIS_N_ROOTS       5
   CIS_MAX_CYCLES    40
   RPA               true
   BASIS             6-31+G*
   SCF_CONVERGENCE   7
$end

Example 7.23  This example shows a calculation of the excited states of a formamide-water complex within a reduced excitation space of the orbitals located on formamide.

$comment
   formamide-water TDDFT/TDA in reduced excitation space
$end

$molecule
   0 1
   H  1.13  0.49 -0.75
   C  0.31  0.50 -0.03
   N -0.28 -0.71  0.08
   H -1.09 -0.75  0.67
   H  0.23 -1.62 -0.22
   O -0.21  1.51  0.47
   O -2.69  1.94 -0.59
   H -2.59  2.08 -1.53
   H -1.83  1.63 -0.30
$end

$rem
   EXCHANGE          b3lyp
   CIS_N_ROOTS       10
   BASIS             6-31++G**
   TRNSS             TRUE
   TRTYPE            1
   CUTOCC            60
   CUTVIR            40
   CISTR_PRINT       TRUE
   N_SOL             6
$end

$solute
1
2
3
4
5
6
$end

Example 7.24  SF-TDDFT SP calculation of the 6 lowest states of the TMM diradical using recommended 50-50 functional.

$molecule
   0 3
   C
   C  1  CC1
   C  1  CC2   2  A2
   C  1  CC2   2  A2     3  180.0
   H  2  C2H   1  C2CH   3    0.0
   H  2  C2H   1  C2CH   4    0.0
   H  3  C3Hu  1  C3CHu  2    0.0
   H  3  C3Hd  1  C3CHd  4    0.0
   H  4  C3Hu  1  C3CHu  2    0.0
   H  4  C3Hd  1  C3CHd  3    0.0

   CC1    = 1.35
   CC2    = 1.47
   C2H    = 1.083
   C3Hu   = 1.08
   C3Hd   = 1.08
   C2CH   = 121.2
   C3CHu  = 120.3
   C3CHd  = 121.3
   A2    = 121.0
$end

$rem
   EXCHANGE          gen
   BASIS             6-31G*
   SCF_GUESS         core
   SCF_CONVERGENCE   10
   MAX_SCF_CYCLES    100
   SPIN_FLIP         1
   CIS_N_ROOTS       6
   CIS_CONVERGENCE   10
   MAX_CIS_CYCLES    100
$end

$xc_functional
   X  HF    0.50
   X  S     0.08
   X  B     0.42
   C  VWN   0.19
   C  LYP   0.81
$end

Example 7.25  SF-TDDFT with non-collinear exchange-correlation functional for low-lying states of CH2.

$comment
  Non-collinear SF-DFT calculation for CH2 at 3B1 state geometry from
  EOM-CCSD(fT) calculation
$end

$molecule
   0 3
   C
   H  1 rCH
   H  1 rCH  2 HCH

   rCH = 1.0775
   HCH = 133.29
$end

$rem
   EXCHANGE             PBE0
   BASIS                cc-pVTZ
   SPIN_FLIP            1
   WANG_ZIEGLER_KERNEL  TRUE
   SCF_CONVERGENCE      10
   CIS_N_ROOTS          6
   CIS_CONVERGENCE      10
$end

Example 7.26  SF-TDDFT calculation with collinear B5050LYP for p-benzyne with wave-function analysis (natural orbitals and NTOs) performed by libwfa.

$comment
Para-benzyne diradical
Equilibrium singlet state geom from:
J. Chem. Phys. 136, 204103 (2012)
Enu = 187.2138176166 hartree
$end

$molecule
   0 3
   H   2.145810  -1.225292   0.000000
   C   1.201382  -0.709285   0.000000
   C   1.201382   0.709285   0.000000
   H   2.145810   1.225292   0.000000
   C   0.000000   1.335664   0.000000
   C  -1.201382   0.709285   0.000000
   H  -2.145810   1.225291   0.000000
   C  -1.201382  -0.709285   0.000000
   H  -2.145810  -1.225291   0.000000
   C   0.000000  -1.335664   0.000000
$end

$rem
   METHOD          = b5050lyp
   BASIS           = 6-31G*
   CIS_N_ROOTS     = 4
   SPIN_FLIP       = true
   NEW_DFT         = true
   STATE_ANALYSIS  = true
   WFA_REF_STATE   = 1
   MOLDEN_FORMAT   = true
   NTO_PAIRS       = 4
$end