Multiwfn forum / Calculating emission spectra

Re: Calculating emission spectra

dummy@example.com (shenaya) — Thu, 27 May 2021 00:59:30 +0000

Thank you.

Re: Calculating emission spectra

dummy@example.com (sobereva) — Tue, 25 May 2021 10:55:06 +0000

This emission is mostly contributed by 147->145 transition (0.682^2*2*100%=93%)

Re: Calculating emission spectra

dummy@example.com (shenaya) — Tue, 25 May 2021 10:41:40 +0000

Dear Tian,

This is a part of the output file for fluorescence emission calculation.

Input : #p opt td=(singlets,root=1) b3lyp/genecp scrf=(solvent=methanol) geom=
connectivity

I have calculated emission spectra. When do orbital contribution calculation I have to consider transition from 145 ---->147 ?
or I understood this wrongly?

Excitation energies and oscillator strengths:

Excited State 1: Singlet-A 1.2577 eV 985.84 nm f=0.0047 =0.000
145 ->147 0.68259
This state for optimization and/or second-order correction.
Total Energy, E(TD-HF/TD-KS) = -3027.47515828
Copying the excited state density for this state as the 1-particle RhoCI density.

Excited State 2: Singlet-A 1.7817 eV 695.89 nm f=0.0001 =0.000
144 ->147 -0.67710

Excited State 3: Singlet-A 1.9683 eV 629.89 nm f=0.0027 =0.000
145 ->146 0.69194
SavETr: write IOETrn= 770 NScale= 10 NData= 16 NLR=1 NState= 3 LETran= 64.
The selected state is a singlet

Re: Calculating emission spectra

dummy@example.com (sobereva) — Fri, 14 May 2021 04:38:39 +0000

No, you can't.

Gaussian is able to calculate emission energy of phosphorescence spectrum, but it is unable to yield oscillator strength of this kind of spectrum (in other words, the printed oscillator strength is always exactly zero), since non-vanishing oscillator strength of T1->S0 emission comes from spin-orbit coupling effect, which cannot be considered by Gaussian at TDDFT level. Usually Dalton program is suggested to compute oscillator strength between T1 and S0.

I cannot understand your second question.

Re: Calculating emission spectra

dummy@example.com (shenaya) — Fri, 14 May 2021 02:46:41 +0000

Hi Tian,

I have successfully plot fluorescence spectra by following the instructions stated by you (http://www.shanxitv.org/wfnbbs/viewtopic.php?id=413).

1. My question is can we plot phosphorescence spectra using exactly same steps?

11 // Plotting spectra
3 // UV-Vis
20 // Modify oscillator strengths
2-3 // Choose S2 and S3 states
0 // Set oscillator strengths to zero (because emission is from S1 state)
0 // Plot spectrum

Becouse phosphorescence is T1---->S0 transition.

Another thing is when people mean emission spectra which one in transition metal complexes.
fluorescence, phosphorescence, or both?

Thank you

Re: Calculating emission spectra

dummy@example.com (shenaya) — Tue, 11 May 2021 01:32:04 +0000

Thank you very much !!!

Re: Calculating emission spectra

dummy@example.com (sobereva) — Fri, 07 May 2021 17:23:15 +0000

Usually, nstates should be at least root+2, where the root is the state of interest. If you optimize S1, then root=1 is of interest, therefore nstates should be >=3. By default, the nstates is just 3, therefore you do not need to alter the default nstates setting. Increasing nstates is not harmful on the result, but higher computational cost is needed.

Re: Calculating emission spectra

dummy@example.com (shenaya) — Fri, 07 May 2021 08:29:57 +0000

Thank you, Tian. Will do it. Generally how many nstates should be used for this type of transition metal complexes.

Re: Calculating emission spectra

dummy@example.com (sobereva) — Fri, 07 May 2021 07:38:24 +0000

Use following keywords for optimizing S1
#p td b3lyp/genecp scrf=(solvent=methanol) geom=connectivity opt

Use following keywords for optimizing T1
#p td(triplet) b3lyp/genecp scrf=(solvent=methanol) geom=connectivity opt

Note that S1 and T1 must be optimized separately, 50-50 cannot be used in this context. guess=save is meaningless. It is unnecessary to set nstates as large as 10, because this will notably increase computational cost while the S1 / T1 will not be detectably affected.

Calculating emission spectra

dummy@example.com (shenaya) — Fri, 07 May 2021 03:56:54 +0000

Dear Tian,

I need to plot emission spectra of Ru transition metal complexes.
This is my input for optimization.
Is this correct?
I need both fluorescence and phosphorescence.
Can I take the output of this calculation to obtain the emission spectra using Multiwfn

%mem=4GB
%nprocshared=4
%chk=Neutral.chk
#p td=(50-50,nstates=10,root=1) b3lyp/genecp scrf=(solvent=methanol)
guess=save geom=connectivity opt

Neutral Fluoride Complex from the X-ray crystal structure

0 1
Ru 0.49152900 -1.00287600 0.09326700
Cl 0.66506000 -1.18796400 -2.33847900
Cl 0.96242300 -1.06595000 2.50569800
P -1.14911300 0.54149000 0.02331800
F 2.76034900 -1.90860800 0.00631700
N 1.77532400 0.64178100 -0.02843200
O -2.22603700 -2.70087200 0.96397000
S -0.87762300 -2.87042900 0.29049200
C 1.27960300 1.90403300 -0.05083200
C -0.13813900 2.08851300 -0.01943800
C -0.64790200 3.36905700 0.00649500
H -1.72172700 3.52421800 0.05440300
C 0.20504300 4.50762600 -0.02719900
H -0.23475300 5.49948700 -0.01111100
C 1.56632600 4.35252600 -0.08013500
H 2.22538600 5.21520600 -0.10762500
C 2.14873400 3.04896800 -0.08989900
C 3.53085900 2.83652700 -0.12465600
H 4.20665800 3.68669100 -0.15556800
C 4.05139700 1.53821100 -0.11568800
C 5.45120700 1.25536100 -0.15050600
H 6.14675600 2.08773100 -0.19077900
C 5.90357800 -0.03875900 -0.13249900
H 6.96691600 -0.25133600 -0.15894000
C 4.98721500 -1.12783200 -0.07836500
H 5.33654100 -2.15449100 -0.06390000
C 3.65038400 -0.86564600 -0.04418000
C 3.11234700 0.44907000 -0.06204300
C -1.19758300 -3.75212800 -1.26942600
H -1.79914200 -4.63222900 -1.02933400
H -0.25052300 -4.02752200 -1.73610500
H -1.74514100 -3.07082800 -1.92117300
C -0.00292000 -4.20020300 1.17802700
H 0.23376000 -3.81407100 2.17029700
H 0.91641400 -4.44979400 0.64186000
H -0.66776000 -5.06540600 1.23910000
C -2.18596100 0.55229000 -1.50150700
C -3.18113500 -0.43327200 -1.62938500
H -3.34446200 -1.14905100 -0.82796800
C -3.96636500 -0.49594700 -2.78073900
H -4.73480500 -1.25924300 -2.86603300
C -3.76744600 0.42012100 -3.81820500
H -4.38023800 0.37087500 -4.71387100
C -2.78018900 1.39921300 -3.69735000
H -2.62036000 2.11581000 -4.49811900
C -1.99099500 1.46594500 -2.54554700
H -1.22701800 2.23231700 -2.46900500
C -2.38962000 0.87519600 1.35444700
C -3.60606500 1.51256500 1.05151600
H -3.85995700 1.75348300 0.02521400
C -4.50566300 1.84038400 2.06810900
H -5.44108100 2.33239300 1.81668500
C -4.20643400 1.53429500 3.39706000
H -4.90946000 1.78576800 4.18632200
C -3.00006700 0.90154900 3.70558200
H -2.76052400 0.65709200 4.73687400
C -2.09536100 0.57430500 2.69378500
H -1.16252800 0.08069500 2.94054800

1 4 1.0 8 1.0
2
3
4 10 1.0 37 1.0 48 1.0
5 27 1.0
6 9 1.5 28 1.5
7 8 1.5
8 29 1.0 33 1.0
9 10 1.5 17 1.5
10 11 2.0
11 12 1.0 13 1.5
12
13 14 1.0 15 2.0
14
15 16 1.0 17 1.5
16
17 18 1.5
18 19 1.0 20 1.5
19
20 21 1.5 28 1.5
21 22 1.0 23 2.0
22
23 24 1.0 25 1.5
24
25 26 1.0 27 2.0
26
27 28 1.5
28
29 30 1.0 31 1.0 32 1.0
30
31
32
33 34 1.0 35 1.0 36 1.0
34
35
36
37 38 1.5 46 1.5
38 39 1.0 40 1.5
39
40 41 1.0 42 1.5
41
42 43 1.0 44 1.5
43
44 45 1.0 46 1.5
45
46 47 1.0
47
48 49 1.5 57 1.5
49 50 1.0 51 1.5
50
51 52 1.0 53 1.5
52
53 54 1.0 55 1.5
54
55 56 1.0 57 1.5
56
57 58 1.0
58

C H P N F S O 0
6-31G(d)
****
Cl
6-31+G(d)
****
Ru 0
SDD
****

Ru 0
SDD

Thanks and regards,
Gayani