Multiwfn forum / TDDFT_T1_excited state optimization

Re: TDDFT_T1_excited state optimization

dummy@example.com (sobereva) — Sun, 11 Jan 2026 22:46:01 +0000

satyam wrote:

How can I plot the potential energy curves and dipole moment curves and know the transition of dipole moment of excited states in Gaussian 16 software?

If you perform potential energy surface scan with an excited state calculation method (for example, using "scan" together with "TD(root=x)" keyword), you will be able to obtain energy and transition dipole moment of state x for every point of the scan coordinate. If you also need dipole moment of the excited state, also try to add "pop=always".

Re: TDDFT_T1_excited state optimization

dummy@example.com (satyam) — Sat, 10 Jan 2026 10:59:21 +0000

How can I plot the potential energy curves and dipole moment curves and know the transition of dipole moment of excited states in Gaussian 16 software?

Re: TDDFT_T1_excited state optimization

dummy@example.com (saroc52) — Sun, 13 Apr 2025 04:55:30 +0000

Thank you professor.

Re: TDDFT_T1_excited state optimization

dummy@example.com (sobereva) — Sat, 12 Apr 2025 17:00:28 +0000

To force ORCA to optimize T1 in the case 2, you should add "irootmult triplet", then the optimization will only consider the triplet excited states.

TDDFT_T1_excited state optimization

dummy@example.com (saroc52) — Sat, 12 Apr 2025 12:51:56 +0000

Hi Dr.Tian Lu and Sobereva

I have been dealing with TADF molecules. Facing an issue with TDDFT triplet state optimization, used optimized groud state geometry for both S1 and T1 TDDFT optimization by usinng orca. Method B3LYP/def2-svp with keyword

! B3LYP def2-SVP Grid6 NoFinalGrid VeryTightSCF OPT Nosym

%TDDFT
NROOTS 3
TDA FALSE
IROOT 1
end

For triplet i used
! B3LYP def2-SVP Grid6 NoFinalGrid VeryTightSCF OPT Nosym

%TDDFT
NROOTS 3
TRIPLETS TRUE
TDA FALSE
IROOT 1
end

After the completion i ended up with almost simialr values and same coordinates..
-------------------------------
TD-DFT EXCITED STATES (SINGLETS)
--------------------------------

the weight of the individual excitations are printed if larger than 0.01

STATE 1: E= 0.038274 au 1.041 eV 8400.1 cm**-1
147a -> 148a : 0.999200

STATE 2: E= 0.059469 au 1.618 eV 13051.9 cm**-1
147a -> 149a : 0.990447

STATE 3: E= 0.085224 au 2.319 eV 18704.5 cm**-1
146a -> 148a : 0.993491

TD-DFT EXCITED STATES (TRIPLETS)
--------------------------------

the weight of the individual excitations are printed if larger than 0.01

STATE 1: E= 0.038137 au 1.038 eV 8370.0 cm**-1
147a -> 148a : 0.998536

STATE 2: E= 0.059028 au 1.606 eV 12955.2 cm**-1
147a -> 149a : 0.984765

STATE 3: E= 0.078299 au 2.131 eV 17184.6 cm**-1
137a -> 151a : 0.015822
143a -> 148a : 0.961806
and RMSD is 0 between S1 and T1 states...
kindly help me to solve the issue that what mistake i does....

Thankyou