Multiwfn forum

rikaaardoss

Member

Registered: 2020-07-29

Posts: 22

regarding conceptual dft analysis and "orbital weighted" indicators

Greetings

When calculating the “Orbital Weighted” reactivity indices using Multiwfn depending on the system being studied and the delta value, it can deliver condensed (and grid) values of 0.0. I understand that this is related to the definition of the indicators, since the values are always very close to zero but there would be a way to “force” the program to calculate with a higher amount of decimals? maybe a modification in the settings.ini file? I know this could lead to a higher computational cost but I am willing to take the risk.

Thank you very much in advance.

R.

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 2,021

Website

Re: regarding conceptual dft analysis and "orbital weighted" indicators

Hello,

I don't exactly know which data you are talking about, could you provide a screenshot?

Best,

Tian

rikaaardoss

Member

Registered: 2020-07-29

Posts: 22

Re: regarding conceptual dft analysis and "orbital weighted" indicators

I apologize for the lack of clarity, I mean specifically when calculating the grid for the orbital weighted dual descriptor and their respective condensed values, when I put a very small delta the values obtained are directly 0, for this reason I can not visualize the cubes in programs like chemcraft nor draw any conclusion with the condensed values.

Many thanks.

R.

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 2,021

Website

Re: regarding conceptual dft analysis and "orbital weighted" indicators

I don't know why you intend to use a very small delta value, perhaps you only want to consider the contribution from the "most" frontier MO? If yes, you can gradually decrease the delta value from the default value 0.1 a.u., each time you can choose "5 Print current orbital weights used in orbital-weighted (OW) calculation" to check the weights.

Taking examples\benzene.fch as example, if the delta is decreased to 0.01 a.u., you will see the following output after choosing option 5

10 Highest weights in orbital-weighted f+ Orbital 22 (LUMO ) Weight: 50.00 % E_diff: 3.410 eV Orbital 23 (LUMO+1) Weight: 50.00 % E_diff: 3.410 eV Orbital 24 (LUMO+2) Weight: 0.00 % E_diff: 5.656 eV Orbital 25 (LUMO+3) Weight: 0.00 % E_diff: 7.147 eV Orbital 26 (LUMO+4) Weight: 0.00 % E_diff: 7.147 eV Orbital 27 (LUMO+5) Weight: 0.00 % E_diff: 7.789 eV Orbital 28 (LUMO+6) Weight: 0.00 % E_diff: 8.202 eV Orbital 29 (LUMO+7) Weight: 0.00 % E_diff: 8.202 eV Orbital 30 (LUMO+8) Weight: 0.00 % E_diff: 8.389 eV Total weight of above listed orbitals: 100.00 % 10 Highest weights in orbital-weighted f- Orbital 21 (HOMO ) Weight: 50.00 % E_diff: -3.410 eV Orbital 20 (HOMO-1) Weight: 50.00 % E_diff: -3.410 eV Orbital 19 (HOMO-2) Weight: 0.00 % E_diff: -5.924 eV Orbital 18 (HOMO-3) Weight: 0.00 % E_diff: -5.924 eV Orbital 17 (HOMO-4) Weight: 0.00 % E_diff: -6.498 eV Orbital 16 (HOMO-5) Weight: 0.00 % E_diff: -8.011 eV Orbital 15 (HOMO-6) Weight: 0.00 % E_diff: -8.011 eV Orbital 14 (HOMO-7) Weight: 0.00 % E_diff: -8.639 eV Orbital 13 (HOMO-8) Weight: 0.00 % E_diff: -9.084 eV Orbital 12 (HOMO-9) Weight: 0.00 % E_diff: -10.752 eV Total weight of above listed orbitals: 100.00 %

Clearly, now only the degenerate two HOMOs and the two LUMOs contribute to orbital weighted Fukui function or dual descriptor.

Best,

Tian