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seonghyun

Member

Registered: 2024-01-04

Posts: 1

Transition dipole moment vector as arrows : opposite direction arrow

Hello everybody,

I'm trying to extract data from section 4.48.11 "Plot transition dipole moment vector contributed by molecular fragments as arrows".
My molecule exhibites a donor-heteroaromatic core-acceptor(=D-pi-A) structure, and I'm approaching one molecule in two cases, but I'm having a problem.

In the first case, the TDM arrow appeared in the direction I thought.
[1. {# opt=calcfc freq b3lyp/6-31++g(d,p) guess=save} /
2. TD-DFT{# td=(singlets,nstates=6,root=1) b3lyp/6-31++g(d,p) guess=save geom=check}]

In the second case, it appeared in the opposite direction.
[1. {# b3lyp/6-31++g(d,p) guess=save geom=connectivity} /
2. TD-DFT{# td=(singlets,nstates=6,root=1) b3lyp/6-31++g(d,p) guess=save geom=check},based on actual molecular structure measured by XRC]

Looking at the isosurface hole and electron distribution, the forward arrow (D to A) seems reasonable, but when checked with VMD, it is the opposite arrow (A to D).

So I checked the log.file and was able to get the following TDM:

Ground to excited state transition electric dipole moments (Au):
       state          X           Y           Z        Dip. S.      Osc.
         1         3.2066      0.1893     -0.0835     10.3252      0.7153

-------------------------------------------------------------------------------------
Ground to excited state transition electric dipole moments (Au):
       state          X           Y           Z        Dip. S.      Osc.
         1        -3.2825     -0.1505      0.0298     10.7986      0.7658

In the second case, is there a simple Tk console command that can change the direction expressed as VMD to the forward direction? or is there a fundamental solution?

Thank you for your reply.
and Happy New Year!

Jang

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,830

Website

Re: Transition dipole moment vector as arrows : opposite direction arrow

Dear Jang,

1 Is there any reason to use guess=save? I think it is not needed.

2 Please note that Gaussian automatically reorientates your system to standard orientation during calculation. Perhaps you want to use "nosymm" keyword to disable this behavior.

Best,

Tian