Large couplings for ET calcs


Click here for full thread
Forum Vet
You may want to try "task dft et" instead of "task scf et". As the orbitals are not optimized, changing the Hamiltonian used to calculate the ET could give weird results.

Bert


Quote:Adsd04 May 26th 10:27 pm
Hi,

I am newer with nwchem and i triying to run some imput test to coupled ET with C-DFT
similiar to some recent reports in the literature. The problems is that the VRP values obtained in my calculations are larger than the values reported for similar molecules in similar calculation conditions. I has been used different inputs models (see atached files) but the problem continue. That is why i turn to you waiting obtain any recommendation to continue with my work
My input is:

start Fc2
title "Fc2 cationico"
echo
charge 1
geometry
C                  3.19286700   -1.79797600   -0.10018600
C 3.63730800 -1.21812200 1.12353800
C 4.51916500 -0.13996100 0.80164200
C 4.60983600 -0.05370300 -0.61878400
C 3.78473000 -1.07851400 -1.17622400
H 3.35407700 -1.53305700 2.11824900
H 3.62435200 -1.26239300 -2.22962700
H 5.01567100 0.50814100 1.51077800
H 5.18393300 0.67312200 -1.17679800
H 2.48778600 -2.61286900 -0.19593200
Fe 2.61500000 0.24507600 0.00078900
C 1.11014000 1.12649000 1.14889200
C 2.02985100 2.11921800 0.70707800
C 2.03480400 2.11659900 -0.71854000
C 1.11809800 1.12226500 -1.16307700
C 0.47961600 0.53873700 -0.00825000
H 0.89577800 0.88000500 2.17929600
H 2.64786700 2.73629600 1.34444400
H 2.65717900 2.73148100 -1.35379400
H 0.91222000 0.87051900 -2.19396500
C -0.47996300 -0.53955600 -0.00819600
C -1.11826400 -1.12330600 -1.16301800
C -2.03532600 -2.11728500 -0.71842100
C -2.03076500 -2.11946100 0.70718700
C -1.11093100 -1.12682800 1.14896200
H -0.91208900 -0.87189800 -2.19392800
H -0.89679500 -0.88006700 2.17934700
H -2.65765200 -2.73222100 -1.35367000
H -2.64909300 -2.73622000 1.34455900
Fe -2.61514600 -0.24527600 0.00033200
C -4.51666800 0.14317500 0.80545200
C -4.61174900 0.05344100 -0.61447400
C -3.78752500 1.07617800 -1.17696100
C -3.19176800 1.79783300 -0.10459700
C -3.63294400 1.22140400 1.12197600
H -5.01151900 -0.50277800 1.51769800
H -5.18807700 -0.67434300 -1.16892000
H -3.34652000 1.53867400 2.11502600
H -3.63008900 1.25715400 -2.23131400
H -2.48631300 2.61188700 -0.20457500
end

basis
H  library 6-31g**
C library 6-31g**
Fe library lanl2dz_ecp
end

ecp
Fe library lanl2dz_ecp
end

dft
xc b3lyp
iterations 500
convergence nolevelshifting
odft
mult 2
cdft 1 20 charge 1.0
cdft 21 40 charge 0.0
vectors output Fc2dador2.mo
end
task dft

dft
xc b3lyp
iterations 500
convergence nolevelshifting
odft
mult 2
cdft 1 20 charge 0.0
cdft 21 40 charge 1.0
vectors output Fc2aceptor2.mo
end
tasK dft

et
vectors reactants Fc2dador2.mo
vectors products Fc2aceptor2.mo
end
task scf et


My output is :


                               -------------------


                          Electron Transfer Calculation
-----------------------------

MO vectors for reactants: Fc2dador2.mo
MO vectors for products : Fc2aceptor2.mo

Electronic energy of reactants     H(RR)   -3167.1137335703
Electronic energy of products H(PP) -3167.1137385630

Reactants/Products overlap S(RP) :  1.14D-01

Reactants/Products interaction energy:
-------------------------------------
One-electron contribution H1(RP) -652.3015883720

Beginning calculation of 2e contribution
Two-electron integral screening (tol2e) : 1.14D-08

Two-electron contribution         H2(RP)     292.3372635365
Total interaction energy H(RP) -359.9643248355

Electron Transfer Coupling Energy |V(RP)|      0.8387068798
184074.857 cm-1
22.822388 eV
526.297 kcal/mol


Thank you very much
Best regards
Andrei