Search found 46 matches

by ankit7540
17 May 2020, 09:44
Forum: Running Dalton
Topic: Seeking suggestions on running MRCI using RAS3 code
Replies: 4
Views: 2131

Re: Seeking suggestions on running MRCI using RAS3 code

Thank you for the comments. Size consistency of the proposed CI (or even RASSCF) approach is a concern. I need polarizabilities over a wide internuclear distance and using rovibrational wavefunctions, I want to compute the relevant transition matrix elements. I have corresponding experimental data f...
by ankit7540
11 May 2020, 11:18
Forum: Running Dalton
Topic: Seeking suggestions on running MRCI using RAS3 code
Replies: 4
Views: 2131

Seeking suggestions on running MRCI using RAS3 code

Dear all, This question goes in tandem with my previous questions on MCSCF/RASSCF ( http://forum.daltonprogram.org/viewtopic.php?f=9&t=1074 ) on this forum. I am trying to run calculation for simple diatomics using RASSCF aiming to get polarizability. Tests with basis sets have shown slow change in ...
by ankit7540
08 May 2020, 07:16
Forum: Running Dalton
Topic: Restarting MCSCF calculation with different basis
Replies: 2
Views: 1155

Restarting MCSCF calculation with different basis

I am trying to rerun a RASSCF calculation with two basis sets for N2. The first calculation goes from HF-> MP2-> RASSCF with the basis cc-pVTZ (this is as suggested on my previous question ( http://forum.daltonprogram.org/viewtopic.php?f=9&t=1074 ). I obtain the output along with the SIRIUS.RST and ...
by ankit7540
12 Apr 2020, 09:29
Forum: Running Dalton
Topic: Calculating response prorperty for more than 30 frequencies
Replies: 4
Views: 624

Re: Calculating response prorperty for more than 30 frequencies

Thank you for the clarification. I do have another question regarding the RESPONSE calculation. For frequencies crossing the electronic absorption we see negative values for polarizability. Are these the real components. Can we also get the Imaginary components, as shown in the figures in the work :...
by ankit7540
12 Apr 2020, 04:53
Forum: Running Dalton
Topic: Calculating response prorperty for more than 30 frequencies
Replies: 4
Views: 624

Calculating response prorperty for more than 30 frequencies

Hello all, It appears that the general RESPONSE section has a limit of 30 frequencies which are accepted at a time. If I try to enter more than 30, only the first 30 cases are included in the calculation. Is this behavior as expected. The calculation finishes without any error though. (Full output f...
by ankit7540
02 Apr 2020, 14:00
Forum: Running Dalton
Topic: Setting thresholds for integral in CASSCF/RASSCF
Replies: 15
Views: 1866

Re: Setting thresholds for integral in CASSCF/RASSCF

Hello Prof. Peter,
Thank you for suggestions regarding orbital occupations. Points (1-3) and (5) are clear to me.
For (4), regarding very small occupation numbers I have a question specific to DALTON.

From the manual I do not see specific parameter for defining these Secondary or Virtual orbitals.
by ankit7540
31 Mar 2020, 08:32
Forum: Running Dalton
Topic: Setting thresholds for integral in CASSCF/RASSCF
Replies: 15
Views: 1866

Re: Setting thresholds for integral in CASSCF/RASSCF

My plan was to make a plot of energies vs the 8 symmetries and look for distinctions for RAS1, RAS2 and RAS3 spaces.
by ankit7540
31 Mar 2020, 08:04
Forum: Running Dalton
Topic: Setting thresholds for integral in CASSCF/RASSCF
Replies: 15
Views: 1866

Re: Setting thresholds for integral in CASSCF/RASSCF

Dear Prof. Jensen, I have tried the suggested dal file for calculation and it finishes very fast. I wonder if we can check the orbital energies after the convergence of the MCSCF wavefunction. Similar to the HF orbital energies (Fock eigenvalues) as following , Hartree-Fock orbital energies, symmetr...
by ankit7540
30 Mar 2020, 11:24
Forum: Running Dalton
Topic: Setting thresholds for integral in CASSCF/RASSCF
Replies: 15
Views: 1866

Re: Setting thresholds for integral in CASSCF/RASSCF

Dear Prof. Taylor and Prof. Jensen, Thank you for the comments. I now understand that the RAS3 space chosen is incorrect. Now running with the suggested RAS3 space. 1. The correlation table for D(inf)h to D2h gives the possible symmetries in D2h and in my case I did not chose RAS3 so that the pairs ...
by ankit7540
26 Mar 2020, 02:11
Forum: Running Dalton
Topic: Setting thresholds for integral in CASSCF/RASSCF
Replies: 15
Views: 1866

Re: Setting thresholds for integral in CASSCF/RASSCF

Hello Dr. Peter,
Thank you for your comments.
The full output file for O2 was uploaded with the original post. It is given here again.
by ankit7540
25 Mar 2020, 11:54
Forum: Running Dalton
Topic: Setting thresholds for integral in CASSCF/RASSCF
Replies: 15
Views: 1866

Re: Setting thresholds for integral in CASSCF/RASSCF

Update 1 : After some testing,

Code: Select all

*SUPINT
.THRESH
does not significantly affect run times. Also it has no effect on the CI coefs.

Update 2: After some testing,

Code: Select all

.Integrals
in the *.mol files also does not significantly reduce run times.
by ankit7540
25 Mar 2020, 10:21
Forum: Running Dalton
Topic: Using electronic wavefunction after NEVPT2 correction for response
Replies: 4
Views: 3086

Re: Using electronic wavefunction after NEVPT2 correction for response

Thank you for this suggestion. I will definitely check about this. ( Usually we are interested in frequency dependent properties since we have experimental data to compare. )
by ankit7540
25 Mar 2020, 10:18
Forum: Running Dalton
Topic: Setting thresholds for integral in CASSCF/RASSCF
Replies: 15
Views: 1866

Setting thresholds for integral in CASSCF/RASSCF

Dear all, I am running MCSCF calculations for finally obtaining good electronic wavefunctions for later response calculations. Convergence of the electronic wavefuction is slow and I am looking for ways to speed things up. I wonder if reducing the threshold for the integrals maybe a good way. From t...
by ankit7540
04 Mar 2020, 06:46
Forum: Running Dalton
Topic: Using electronic wavefunction after NEVPT2 correction for response
Replies: 4
Views: 3086

Using electronic wavefunction after NEVPT2 correction for response

Dear All, After applying NEVPT2 correction to mcscf wavefunctions, significant reduction in energy is observed. However, the subsequent response calculation falls back to the mcscf wavefunction giving no improvement in the properties. Hence, the question. Can we use the electronic wavenfunction afte...
by ankit7540
12 Nov 2019, 07:10
Forum: Running Dalton
Topic: RESPONSE under CI calculation : ERROR (MOLLAB) MOLECULE label not found
Replies: 2
Views: 1668

Re: RESPONSE under CI calculation : ERROR (MOLLAB) MOLECULE label not found

Dear Prof. Jensen,
Thank you for the reply.
If I understand correctly, I should now include 3s, 3p and possibly 3d orbitals, in the active space for the CI calculation. I guess that should improve the polarizability for CI method.
by ankit7540
08 Nov 2019, 03:15
Forum: Running Dalton
Topic: RESPONSE under CI calculation : ERROR (MOLLAB) MOLECULE label not found
Replies: 2
Views: 1668

RESPONSE under CI calculation : ERROR (MOLLAB) MOLECULE label not found

Hello, I am trying to obtain ground state properties for O2, starting with mcscf (CAS 12) and possibly moving to CI. In this regard, it seems that the wavefunction part of the calculation runs fine, but problems occur for RESPONSE module for CI. ( for mcscf, RESPONSE runs ok and the values of polari...
by ankit7540
30 Nov 2017, 03:56
Forum: Running Dalton
Topic: Tested DFT functionals for linear, quadratic and cubic response in DALTON2016
Replies: 0
Views: 8518

Tested DFT functionals for linear, quadratic and cubic response in DALTON2016

Hello all, This is a follow up question to this previous question asked in 2013 ( http://forum.daltonprogram.org/viewtopic.php?f=9&t=253&p=1667&hilit=functional+not+fully+implemented%2Ftested+for+QR#p1667 ) For DALTON 2016, which of the DFT functionals are tested for linear, quadratic and cubic resp...
by ankit7540
26 Nov 2017, 06:19
Forum: Running Dalton
Topic: Optimization followed by vibrational analysis (numerical) with CCSD
Replies: 4
Views: 4273

Re: Optimization followed by vibrational analysis (numerical) with CCSD

Hello,
You are correct. I confirmed that the program does the vibrational analysis using HF and not the CC wavefunctions. Thanks for the clarification.

Ankit
by ankit7540
22 Nov 2017, 13:16
Forum: Running Dalton
Topic: Optimization followed by vibrational analysis (numerical) with CCSD
Replies: 4
Views: 4273

Re: Optimization followed by vibrational analysis (numerical) with CCSD

Hello,
With the **PROPERTIES keyword the .VIBANA analysis works fine as shown in the attached output file ( and the program gave me the hessian as I asked for).
ccsd_freq_water_singleOpt_DZ.out
Frequency analysis only with **PROPERTIES and .VIBANA
(63.5 KiB) Downloaded 330 times
by ankit7540
18 Nov 2017, 06:56
Forum: Running Dalton
Topic: Optimization followed by vibrational analysis (numerical) with CCSD
Replies: 4
Views: 4273

Optimization followed by vibrational analysis (numerical) with CCSD

Hello all, I can easily run independent optimization and vibrational analysis (using numerical derivatives) using CCSD using two separate calculations. However, I wonder if it is possible to combine these. Hence, first run optimization, and if the optimization succeeds then do vibrational analysis, ...
by ankit7540
01 Jul 2017, 06:55
Forum: Running Dalton
Topic: Negative polarizability for H2 at larger r ( freq. dependent )
Replies: 2
Views: 3497

Re: Negative polarizability for H2 at larger r ( freq. dependent )

Dear Kenneth Ruud,
Thank you very much for the manuscript.