Large couplings for ET calcs
Clicked A Few Times
12:22:08 PM PDT - Mon, Oct 17th 2011
I've been seeing some very large couplings when running the et task, and so I decided to try the example in the manual, a self-exchange reaction with He/He+ ([1]) with NWChem version 6.0. I tried two runs, one with the He 5 Angstroms apart, and one @ 10 Angstroms apart. Basis set was Ahlrichs_pVDZ, from the library.

I don't know what the geometry or basis were for the example given in the documentation. For reference the values are given as


Electronic energy of reactants     H(RR)      -5.3402392824
Electronic energy of products      H(PP)      -5.3402392824
Reactants/Products overlap         S(RP)      -0.0006033839
One-electron contribution         H1(RP)       0.0040314092
Two-electron integral screening (tol2e) : 6.03E-11
Two-electron contribution         H2(RP)      -0.0007837138
Total interaction energy           H(RP)       0.0032476955
Electron Transfer Coupling Energy |V(RP)|      0.0000254810
                                                      5.592 cm-1
                                                   0.000693 eV
                                                      0.016 kcal/mol


For 5 A, I see
 Electronic energy of reactants     H(RR)      -3.1919485760
 Electronic energy of products      H(PP)      -3.1919485759
 Reactants/Products overlap S(RP) :  1.00D+00
 One-electron contribution         H1(RP)      -4.6181893392
 Two-electron integral screening (tol2e) : 6.03D-11
 Two-electron contribution         H2(RP)       1.4262407635
 Total interaction energy           H(RP)      -3.1919485757
 Electron Transfer Coupling Energy |V(RP)|      2.1006474897
                                                  461038.768 cm-1
                                                   57.161559 eV
                                                    1318.177 kcal/mol


For 10 A, I see
 Electronic energy of reactants     H(RR)      -2.9537597557
 Electronic energy of products      H(PP)      -2.9537597556
 Reactants/Products overlap S(RP) :  1.00D+00
 One-electron contribution         H1(RP)      -4.3005260783
 Two-electron integral screening (tol2e) : 6.03D-11
 Two-electron contribution         H2(RP)       1.3467663226
 Total interaction energy           H(RP)      -2.9537597556
 Electron Transfer Coupling Energy |V(RP)|      0.7327601032
                                                  160822.231 cm-1
                                                   19.939428 eV
                                                     459.814 kcal/mol

Although the trend is as expected (coupling goes down with distance; @ tol2e=default 1e-7, the opposite happened), the couplings are much too large. Also, S=1, unlike the small negative number in the example.
Thanks for any help.


Input for the 5A job was:


start 8TNaEwO57SmBqwjO
permanent_dir /scratch/scratchdirs/cchang/8TNaEwO57SmBqwjO/perm
scratch_dir /scratch/scratchdirs/cchang/8TNaEwO57SmBqwjO/scr
ECHO
TITLE "Test for ET module os NWChem"

geometry He nocenter noautoz
  He 0.0   0.0   0.0
end

geometry HeP nocenter noautoz
  He 5.0   0.0   0.0
end

geometry HeHeP nocenter noautoz
  He 0.0   0.0   0.0
  He 5.0   0.0   0.0
end

basis "ao basis" cartesian
   * library "Ahlrichs_pVDZ"
end

scf
   singlet; uhf; vectors input atomic output He.movecs
end
charge 0
set geometry He
task scf

scf
   doublet; uhf; vectors input atomic output HeP.movecs
end
charge 1
set geometry HeP
task scf

#ET reactants:
scf 
  doublet; uhf; vectors input fragment He.movecs HeP.movecs output HeA.movecs
end 
set geometry HeHeP
task scf

#ET products:
scf 
  doublet; uhf; vectors input HeA.movecs reorder 2 1 output HeB.movecs
end 
task scf

et
 tol2e 6.03e-11
 vectors reactants HeA.movecs 
 vectors products HeB.movecs
end
task scf et

Forum Vet
12:52:48 PM PDT - Mon, Oct 17th 2011
An overlap between the reactant and product being 1 obviously means that the orbitals for both the reactant and product are the same, i.e. the electron has not been moved from one atom to the other. You can easily check this by looking at the changes and populations at the end of the reactant and product SCF runs. The following input deck works fine for me.

Bert



start chang
ECHO
TITLE "Test for ET module os NWChem"

basis "ao basis" cartesian
  * library "Ahlrichs_pVDZ"
end

geometry
He 0 0 0
end

charge 1

scf
uhf

doublet

vectors output HeP.movecs
end
task scf

charge 0

scf
uhf

singlet

vectors output He.movecs
end
task scf

geometry noautosym noautoz
 He 0.0   0.0   0.0

 He 5.0   0.0   0.0
end

charge 1
  1. ET reactants:
scf
 doublet; uhf; vectors input fragment HeP.movecs He.movecs output HeA.movecs
end
task scf

  1. ET products:
scf
 doublet; uhf; vectors input HeA.movecs reorder 2 1 output HeB.movecs
end
task scf

et
vectors reactants HeA.movecs

vectors products HeB.movecs
end
task scf et



Quote:Cchang Oct 17th 7:22 pm
I've been seeing some very large couplings when running the et task, and so I decided to try the example in the manual, a self-exchange reaction with He/He+ ([1]) with NWChem version 6.0. I tried two runs, one with the He 5 Angstroms apart, and one @ 10 Angstroms apart. Basis set was Ahlrichs_pVDZ, from the library.

I don't know what the geometry or basis were for the example given in the documentation. For reference the values are given as


Electronic energy of reactants     H(RR)      -5.3402392824
Electronic energy of products      H(PP)      -5.3402392824
Reactants/Products overlap         S(RP)      -0.0006033839
One-electron contribution         H1(RP)       0.0040314092
Two-electron integral screening (tol2e) : 6.03E-11
Two-electron contribution         H2(RP)      -0.0007837138
Total interaction energy           H(RP)       0.0032476955
Electron Transfer Coupling Energy |V(RP)|      0.0000254810
                                                      5.592 cm-1
                                                   0.000693 eV
                                                      0.016 kcal/mol


For 5 A, I see
 Electronic energy of reactants     H(RR)      -3.1919485760
 Electronic energy of products      H(PP)      -3.1919485759
 Reactants/Products overlap S(RP) :  1.00D+00
 One-electron contribution         H1(RP)      -4.6181893392
 Two-electron integral screening (tol2e) : 6.03D-11
 Two-electron contribution         H2(RP)       1.4262407635
 Total interaction energy           H(RP)      -3.1919485757
 Electron Transfer Coupling Energy |V(RP)|      2.1006474897
                                                  461038.768 cm-1
                                                   57.161559 eV
                                                    1318.177 kcal/mol


For 10 A, I see
 Electronic energy of reactants     H(RR)      -2.9537597557
 Electronic energy of products      H(PP)      -2.9537597556
 Reactants/Products overlap S(RP) :  1.00D+00
 One-electron contribution         H1(RP)      -4.3005260783
 Two-electron integral screening (tol2e) : 6.03D-11
 Two-electron contribution         H2(RP)       1.3467663226
 Total interaction energy           H(RP)      -2.9537597556
 Electron Transfer Coupling Energy |V(RP)|      0.7327601032
                                                  160822.231 cm-1
                                                   19.939428 eV
                                                     459.814 kcal/mol

Although the trend is as expected (coupling goes down with distance; @ tol2e=default 1e-7, the opposite happened), the couplings are much too large. Also, S=1, unlike the small negative number in the example.
Thanks for any help.


Input for the 5A job was:


start 8TNaEwO57SmBqwjO
permanent_dir /scratch/scratchdirs/cchang/8TNaEwO57SmBqwjO/perm
scratch_dir /scratch/scratchdirs/cchang/8TNaEwO57SmBqwjO/scr
ECHO
TITLE "Test for ET module os NWChem"

geometry He nocenter noautoz
  He 0.0   0.0   0.0
end

geometry HeP nocenter noautoz
  He 5.0   0.0   0.0
end

geometry HeHeP nocenter noautoz
  He 0.0   0.0   0.0
  He 5.0   0.0   0.0
end

basis "ao basis" cartesian
   * library "Ahlrichs_pVDZ"
end

scf
   singlet; uhf; vectors input atomic output He.movecs
end
charge 0
set geometry He
task scf

scf
   doublet; uhf; vectors input atomic output HeP.movecs
end
charge 1
set geometry HeP
task scf

#ET reactants:
scf 
  doublet; uhf; vectors input fragment He.movecs HeP.movecs output HeA.movecs
end 
set geometry HeHeP
task scf

#ET products:
scf 
  doublet; uhf; vectors input HeA.movecs reorder 2 1 output HeB.movecs
end 
task scf

et
 tol2e 6.03e-11
 vectors reactants HeA.movecs 
 vectors products HeB.movecs
end
task scf et

  • Guest -
5:00:44 PM PDT - Tue, Oct 18th 2011
Hi Bert,

  Thanks, I could get it with your deck. I figured the overlap was symptomatic of the problem, but I was expecting an Inf (or stars) coupling if the overlap were really 1.0 between the reactant and product wavefunctions. It came down to requiring "noautosym" to be present. Now I see, symmetrizing the wavefunctions forced the solutions to delocalize despite the localized fragment guess.

Thanks again!

Just Got Here
3:27:08 PM PDT - Sat, May 26th 2012
coupled ET with C-DFT
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

Forum Vet
2:52:46 PM PDT - Wed, May 30th 2012
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

Just Got Here
10:44:18 AM PDT - Thu, May 31st 2012
NWChem will skip this task
hi , Bert
thank you, but what happens is Electron Transfer for DFT has not been implemented in NWChem 6.1 , or so writing in the output, if i triying to run some input with "task dft et"

                               NWChem Input Module

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




Electron Transfer for DFT has not been

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

 implemented. NWChem will skip this task!.

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

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

dft et failed                                                                           0

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

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

 current input line :

   84: task dft et

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

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

This type of error is most commonly associated with calculations not reaching

convergence criteria

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

For more information see the NWChem manual at

http://nwchemgit.github.io/index.php/NWChem_Documentation




For further details see manual section:

Forum Vet
3:22:08 PM PDT - Thu, May 31st 2012
My bad. The current ET has only been implemented for SCF. What you can do is the following:

dft
 xc hfexch

 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 hfexch

 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


Doing some research, I think what you are trying to do is the calculation of the coupling matrix element with CDFT as outlined in the Wu and Van Voorhis JCP 2006 paper. My understanding is that this did not get integrated into the NWChem code. I am communicating with them right now to see if we can get this integrated for the next release.

Thanks,

Bert

Quote:Adsd04 May 31st 5:44 pm
hi , Bert
thank you, but what happens is Electron Transfer for DFT has not been implemented in NWChem 6.1 , or so writing in the output, if i triying to run some input with "task dft et"

                               NWChem Input Module

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




Electron Transfer for DFT has not been

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

 implemented. NWChem will skip this task!.

Electron Transfer for DFT has not been

 implemented. NWChem will skip this task!.

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

dft et failed                                                                           0

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

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

 current input line :

   84: task dft et

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

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

This type of error is most commonly associated with calculations not reaching

convergence criteria

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

For more information see the NWChem manual at

http://nwchemgit.github.io/index.php/NWChem_Documentation




For further details see manual section:[/quote]

Clicked A Few Times
5:56:46 PM PDT - Mon, Jul 8th 2013
Hi Bert,

Is that 'task dft et' implemented on any newer version or any available patch for this module?

Thank you
Mahbub

Forum Vet
12:31:31 PM PDT - Tue, Jul 9th 2013
Quote:Mahbub03 Jul 8th 4:56 pm
Hi Bert,

Is that 'task dft et' implemented on any newer version or any available patch for this module?

Thank you
Mahbub


No, it has not been implemented.

Cheers, Edo

Clicked A Few Times
8:46:06 AM PST - Sun, Dec 6th 2015
constaint charge
Hello

How can I determine?

cdft 1 20 charge 0.0



cdft 21 40 charge 1.0


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