Hi all! I am new to ORCA. Can any one help in how to setup an ORCA input file for calculate optical rotation of chiral molecule?

More Prasanta Nag's questions See All

How can we draw the graph of a function of complex variables involving two variables in Matlab?

Suppose the function is $f(z_1, z_2) = z_1^2+z_2^2$, where $z_1, z_2 \in \mathbb{C}$. How to implement the graph in Matlab in an given interval. Can anyone help?

11 January 2021 1,018 2 View

Physical significance of Gap between optical and acosutic branches in Phonon Dispersion?

Hello Everyone, Recently I am doing some Phonon branchesbased studies. For some materials the gap between the optical and acoustic branch is small, for some it's large and for some there is no...

04 November 2020 3,987 2 View

Can I perform islet isolation after storing the excised mouse pancreas for 3 months and what is the protocol for this process?

I have sacrificed treated BALB/C mice and collected the pancreas and stored in -20 degree centigrade for 3 months. Now I want to isolate the islets to study the release of different cytokines from...

08 October 2020 7,299 6 View

Anyone please suggest reference and scitation tool comaptible with WPS or Libreoffice?

Hello Researchers, I mostly use WPS and Libreoffice but the problem which is face several times is addinf references and citations. Because even when we change one of the reference it doesn't get...

23 April 2020 4,962 8 View

Hello everyone. my question is why electric vehicle need reactive power and sometimes EV also provide reactive power support to grid.Explain how?

many literature talked about reactive power support to EV by distribution grid and vice versa. But EV load is nothing but charging a battery, which is a pure DC load or source.

07 March 2020 6,787 3 View

How can electrostatic energy becomes positve while the total energy is negative in LMOEDA?

I my study of intermolecular non-covalent complexes, I have used LMO-EDA by GAMESS codes to find the seperate contributions of energy terms. In a strange finding, I observed that although total...

23 November 2019 7,396 9 View

How can determine the Quantity of liquid desiccant for air dehumidification system? Required Temperature for Regeneration??

Liquid Desiccant air dehumidification System Design with regeneration

24 June 2019 2,341 1 View

How to rectify negative triplet energy using Gaussian 09, A.02 ?

While doing the vertical excitation energy calculation in gas phase, I got a negative triplet energy. Can anyone suggest on how to rectify this?

14 May 2019 8,731 3 View

Tris-HCl buffer with MgCl2 turns brown?

I am preparing 10mM Tris-HCl buffer for DNA aptamer with 200 mM NaCl, 25mM KCl, 10mM MgCl2 and a pH of 8. Because of the presence of MgCl2, the buffer is turning brown. Is it normal for the color...

30 June 2018 6,533 3 View

Can anyone help me to find the literature on matrix pencils arising in linear Quadratic optimal control problems?

I want to study the matrix pencils which occur during solving optimal control theory problems.

29 May 2018 2,035 2 View

Tried to do Freq calculation for a organic molecule in ORCA but the calculation is still running. What should be the steps to make it faster?

I am running Freq calculation combined with optimization of a molecule having 14 carbon atom but the calculation is still now running since 3 days. I also have done only optimization of the same...

22 August 2020 2,004 3 View

Solve the problem ORCA error running (CoPc(OH)16)?

Hello, I did a running iron and cobalt phthalocyanine compound plus functional groups -OH (FePc(OH)16) & (CoPc(OH)16) with ORCA using Gabedit. when running CoPc with use: # CoPcOH16 ! B3LYP...

11 August 2020 9,990 2 View

Why in TDDFT, some of the output for the first state has a negative wavelength and oscillator strength ?

I'm doing TDDFT calculation. I have calculated excited state calculation for n=20 states. The first state (lowest in energy) showing negative wavelength and oscillator strength. How we can explain...

11 August 2020 6,788 4 View

ORCA4.2.0 GTOInt error?

when I run ORCA, I got an error as follows: ORCA finished by error termination in GTOInt Calling Command: mpiexec -np 4 D:\ORCA421\orca_gtoint_mpi.exe na20.int.tmp na20 [file...

08 May 2020 5,444 3 View

How to find/predict transcription factors for a putative promoter of the gene of my interest?

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21 February 2020 3,035 3 View

How can electrostatic energy becomes positve while the total energy is negative in LMOEDA?

I my study of intermolecular non-covalent complexes, I have used LMO-EDA by GAMESS codes to find the seperate contributions of energy terms. In a strange finding, I observed that although total...

23 November 2019 7,396 9 View

How can electrostatic energy becomes positve while the total energy is negative in LMOEDA?

I my study of intermolecular non-covalent complexes, I have used LMO-EDA by GAMESS codes to find the seperate contributions of energy terms. In a strange finding, I observed that although total...

10 November 2019 3,703 9 View

How do derive force constants from QM into MD for drugs and small compounds?

Hi, I know the fundamentals, I'm would like an update on the available open-source software. I have a set of small molecules and drug molecules. I've derived their ground state structure using...

10 November 2019 9,586 3 View

How to calculate triplet excited states using DFTB+?

Hi. I'm new in using DFTB but have some experience in other packages like ORCA. I was looking for a simple example (input file) for calculating singlet and triplet excited states of a molecule...

15 October 2019 9,626 1 View

How to calculate triplet excited states using DFTB+?

Hi. I'm new in using DFTB but have some experience in other packages like ORCA. I was looking for a simple example (input file) for calculating singlet and triplet excited states of a molecule...

09 October 2019 6,033 1 View

Sihan Zhang

I like to use ASE and VS to get an input file. You can install them and find some introductions on the internet. If you have the experience of running other programs, I personally suggest you to learn about the structure of an input file. That is pretty easy. the structure data can get from other program like gview. What you need is just remember some keywords.

By the way, I have sent you a copy of manual of ORCA by message box, you can find keywords on it. Wish it will help.