Hi

I would like to know about the GDD tuning procedure.

I am familiar with IP and EA tuning methods but very new to GDD. In the IP and EA tuning procedure, we perform neutral optimization and single-point energy calculations for cationic and anionic geometry. We put all the values in the J(ω) equation to the minimum error omega value.

Can anyone tell me about the GDD tuning procedure? I want to try it for conjugated systems.

I want to know the technical things. Is it also an optimization method? How can we proceed with this method?

I checked the Q-chem manual example. From there, it is not clear to me.

It is described here:

with references to the original literature

Hi

I tried to run a job with the GDD tuning procedure.

$rem

BASIS = cc-pvdz

EXCHANGE = LRC-wPBEh

MAX_CIS_CYCLES = 400

SCF_CONVERGENCE = 8

MAX_SCF_CYCLES = 400

sts_mom = true

THRESH = 14

UNRESTRICTED = true

SPIN_FLIP = true

JOB_TYPE = optimization

omega = 200

omega_gdd = true

lrc_dft = true

CIS_N_ROOTS = 5

cis_state_derivative = 1

SYMMETRY_IGNORE = true

SYMMETRY = false

SOLVENT_METHOD = PCM

$end

$solvent

DIELECTRIC 7.5

OPTICALDIELECTRIC 1.40

$end

##
but in output job ended with no error:

Cartesian Multipole Moments

```
Charge (ESU x 10^10)
0.0000
Dipole Moment (Debye)
X -0.0002 Y 0.0001 Z 0.0003
Tot 0.0003
Quadrupole Moments (Debye-Ang)
XX -170.2931 XY -11.5858 YY -153.0227
XZ -2.0189 YZ -5.0246 ZZ -163.5121
Octopole Moments (Debye-Ang^2)
XXX -1943.7921 XXY -88.1646 XYY -582.2261
YYY 0.0022 XXZ -1454.1026 XYZ -117.0075
YYZ -1292.8328 XZZ -656.2634 YZZ -84.9065
ZZZ -4144.4214
Hexadecapole Moments (Debye-Ang^3)
XXXX -20025.7595 XXXY 281.6123 XXYY -3369.2753
XYYY 812.3797 YYYY -2195.8264 XXXZ -16769.0481
XXYZ -835.1369 XYYZ -4916.9071 YYYZ 47.0203
XXZZ -16547.8607 XYZZ -884.3330 YYZZ -12229.7039
XZZZ -16050.6184 YZZZ -1000.2364 ZZZZ -75579.0995
```

Calculating analytic gradient of the CIS energy

PCM in get_w_cis.C

CIS relaxed dipole moment

1

1 -0.0000070

2 0.0000152

3 -0.0001037

Magnitude: 0.000 au 0.000 Debye

Is it an optimization method? Can you please help me with how I will proceed with this method?

Probably some of these options are incompatible. When you encounter a problem like this, it’s helpful if you can strip down your example and isolate what clash of input options are causing the problem, rather than having so many different things turned on at once. That’s also a good idea because you don’t seem to understand what kind of a calculation you have requested.

As an example of what I mean by isolating the problem, I created this stripped-down input file:

```
$rem
jobtype opt
method b3lyp
basis 6-31G
lrc_dft true
omega 300
omega_gdd true
!cis_n_roots 1
!cis_state_deriv 1
$end
$molecule
0 1
O
H 1 0.95
H 1 0.995 2 104.5
$end
```

As written, this runs w/o problem but if I uncomment the two CIS keywords, it fails in the manner that you described. This tells me there is a conflict between excited-state optimization and wGDD. (Specifically optimization, or rather the gradient, because a single-point excited-state calculation runs fine with wGDD.)

I will submit a bug ticket to document this, but I think what you are (seemingly) trying to do is not a good idea, namely, changing the omega parameter at each step of an optimization w/o putting any thought into it. I suggest that you reconsider your computational strategy.