Multiwfn forum / chemical bond in excited states using Multiwfn and Orca

Re: chemical bond in excited states using Multiwfn and Orca

dummy@example.com (sobereva) — Sat, 26 Mar 2022 10:05:37 +0000

rikaaardoss wrote:

So, from what I understand, there is no way to obtain the wave function of the system in the excited state T1, but I could only study it in T0.

You should set both first and second states with weight of 0.5. Then both the states should be able to solve.

Re: chemical bond in excited states using Multiwfn and Orca

dummy@example.com (rikaaardoss) — Sat, 26 Mar 2022 08:58:24 +0000

So, from what I understand, there is no way to obtain the wave function of the system in the excited state T1, but I could only study it in T0.

Re: chemical bond in excited states using Multiwfn and Orca

dummy@example.com (sobereva) — Sat, 26 Mar 2022 08:50:57 +0000

Usually, to calculate excited state by CASSCF, you should use state-average treatment, otherwise due to variational collapse, despite you set initial weight of T1 as 1.0, the wavefunction may finally converge to T0.

chemical bond in excited states using Multiwfn and Orca

dummy@example.com (rikaaardoss) — Sat, 26 Mar 2022 08:39:55 +0000

Hi all, I am interested in analyzing chemical bonding in excited states using Multiwfn. For this I have done casscf calculations in ORCA, the system I am studying is triplet in its ground state (T0), however I am not getting the wave function of the first triplet excited state (T1), is there any way to obtain this function?, here is the input I am using:

! def2-TZVP def2/J
! moread
%moinp "c2o_t.gbw"
%MaxCore 20000
%scf
TolG 1.0e-04
TolE 1.0e-06
maxiter 500
end
%casscf
nel 14
norb 10
mult 3
nroots 3
weights[1] = 1.0,0.0,0.0
end

%pal nprocs 10
end
*xyz 0 3
C 0.000000000 0.000000000 0.000000000
C 0.000000000 -1.369900105 0.000000000
O 0.000000000 1.162700089 0.000000000

I figured I should change the weight of the state, so I would have this: " weights[1] = 0.0,1.0,0.0 "

However, when I get the molden file and check the occupancies of the natural orbitals both files are very similar.

Thanks advance for any help provided.