Questions tagged [gaussian]

For questions related to the Gaussian electronic structure program

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How to restart an interrupted TS optimization job in Gaussian16 without the CalcFC option from the chk file?

I have to do the TS optimization of a very large structure. Initially, I used the typical opt(ts,calcfc,noeigentest) at the route section, but during the ...
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4 votes
3 answers
509 views

Convert .xyz format to Gaussian Input file (.gjf)

I have a .xyz file, and I would like to change the format to .gjf (Gaussian Input File) by converting the name of format. Do you know how to prevent my situation? (Originally I talked about 'gif' and '...
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6 votes
2 answers
404 views

Do bonds between the atoms influence ab-initio energies?

As you know, oxygen has two available states. However, the picture above illustrates oxygen (red) has a just one bonding with one carbon. I am kind of afraid it makes differences compared that an ...
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1 vote
0 answers
14 views

Gaussian(Software): What does atomic orbital contribution mean?

Example Molecule: C60 (Fullerene) Route Section: #p B3LYP/6-311G(d) guess = read geom = check pop = full Question: What information can I get from atomic orbital contributions? I've calculated atomic ...
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3 votes
1 answer
39 views

Determining orbital occupation through MO shape (Biorthogonalized molecular orbital)

Can it be determined whether a biorthogonalized molecular orbitals is singly occupied just from its shape? You can see the picture below, describing biorthogonalized molecular orbitals' shapes of $\ce{...
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2 votes
1 answer
105 views

Cause of segfault from simple Gaussian16 input?

First of all, I already did electronic structure calculations in the past, but I am a total beginner regarding the use of Gaussian. Currently I am trying to use Gaussian16 through the terminal on ...
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2 votes
0 answers
20 views

Gaussian Job File with Variables and Link1

I work now with larger job files and use the --Link1-- keyword to organize up to 10 jobs in one job file. This works very well for me. But I got a lot of job series ...
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2 votes
0 answers
26 views

Installation of GaussView on Linux Ubuntu 20.04.2 ARM

Has someone made some experience with installing GaussView for Linux on an Ubuntu ARM64 virtuelle maschine? I work with an Mac M1 Chip MacBook Pro and GaussView is the only program I need to run on ...
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2 votes
0 answers
28 views

How to solve "step out of bounds" error in Gaussian?

I am trying to optimize a molecular geometry with Gaussian 16 and this is the line of instructions: ...
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2 votes
1 answer
65 views

A different way to optimize triplets?

I am studying a system with TD-DFT method implemented in Gaussian. I am not sure whether this two inputs are adequate by the mean of output - optimization of T1? ...
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5 votes
0 answers
36 views

How does TD-DFT optimization proceeds in Gaussian?

I am ambiguous in understanding how does Gaussian actually run the TD-DFT optimization. For the explanatory purposes I attach two files: td=triplets.log, which ...
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4 votes
0 answers
45 views

Searching for advices in excited singlet and triplet state optimization

I am using Gaussian16 (revC.01) to optimize several singlet and triplet excited states of the system built up of H, C, N and Ru atoms. It is quite large (~70 atoms). The level of theory I use is M06, ...
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4 votes
0 answers
41 views

Localising radicals on groups or atoms in Gaussian

I am interested in computing single point interaction energy between monomers of radicals located specifically on certain groups or atoms. I have been looking at forums and so and it seems that it is ...
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3 votes
1 answer
144 views

DFT-D2 calculations in VASP and Gaussian

We are planning on comparing the results of Quantum dots and Bulk materials for our systems so we are planning to use Gaussian for QD and VASP for Bulk. Considering that we will be comparing their ...
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5 votes
1 answer
48 views

How to modify Gaussian Z-matrix to adjust distances between monomers

I am trying to make a script to adapt and modify the distances between two monomers I do have. I have build a xyz structure and use Openbabel to construct the Z-matrix of the system. However, I am not ...
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5 votes
1 answer
65 views

IRC (intrinsic reaction coordinate) "RxCoord" calculation in Gaussian

I'm running an IRCs calculation on the TS (transition state) in Gaussian, and I see this table at the end of the calculation with the following header: ...
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4 votes
0 answers
40 views

Optimization converged but frequency calculation does not

I tried a three-step job file for gaussian. This is my input file: ...
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4 votes
2 answers
393 views

Find with grep in terminal last hit in log file

I use grep to find the string "Converged?" with the terminal in several folders to read the output from my gaussian ...
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6 votes
1 answer
100 views

How exactly are valence orbitals combined in split valence basis sets such as 3-21G?

For hydrogen, the 3-21G basis set (in CFOUR format) is ...
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5 votes
1 answer
72 views

How to run SCRF in Gaussian with extra basis?

I want to run a SCRF calculation in Gaussian for a molecule. This has been done as standard with several geometries without issue using the aug-cc-pvtz basis and ...
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1 vote
0 answers
111 views

Error: hangup in Gaussian 09

I have the following problem to run a calculation using Gaussian 9. The calculation starts running and after a few hours stop. The nohup file has the following ...
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6 votes
0 answers
73 views

Optimizing (DFT/MP2) small molecule dimers

I'm attempting to optimize n-alkane dimers using MP2/DFT in Gaussian09. However the first one or two frequencies are always negative. Can these modes be ignored or do I need to do a tighter ...
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3 votes
0 answers
370 views

Gausian 09 error: NtrErr Called from FileIO

I got below mentioned error while trying to optimise a Ru transition metal complex using 6-311++G(d,p) Can you please assist me to resolve this problem ...
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3 votes
1 answer
55 views

Calculate the atomic charge for transition metal using RESP?

I calculate the atomic charge using restricted electrostatic potential (RESP) and compute with the Hartree Fock method. This method is OK for organic compounds, but for complexes that contain ...
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7 votes
1 answer
92 views

Fitting GTOs to other density/wavefunction representations - state of the art?

When using most molecular electron structure codes that use GTOs for the density or wavefunction, it is possible to project the first-order density matrix onto 'natural orbitals' with MOs expressed ...
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8 votes
1 answer
225 views

Restart potential energy scan in Gaussian with additional scan points

I have finished a scan of a bond length, but I need to continue the coordinate scan adding more points to the same scan. I thought of writing a second input file from the last geometry, relaunching ...
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9 votes
1 answer
81 views

Too large value of s-orbital in near nucleus

After my previous question (here), I'm now studying the orbitals actually used in Gaussian through calculating them myself using Basis Set Exchange data. However, I found that some orbital exponents ...
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6 votes
1 answer
200 views

How to generate a 3D electron density surface from fchk file using GaussView 6 without Gaussian

I tried to generate a density surface (the one from red to blue) for Clothianidin, but GaussView 6 gives me errors. I am using GaussView 6.0 without Gaussian installed on the same machine. Gaussian16 ...
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6 votes
1 answer
404 views

Gaussian Inv3 Error

Does somebody know how to resolve the error Inv3 failed in PCMMkU. Error termination via Lnk1e in /g16/g16/l502.exe at Sat Jan 15 19:18:03 2022. The input is <...
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7 votes
1 answer
80 views

Loop calculation in Gaussian

I want to run multiple jobs on Gaussian using windows. I know it is possible to do so on Linux. But can we perform a loop in Gaussian with Windows? In my calculation, I need to use the optimized ...
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  • 517
9 votes
3 answers
231 views

The number of orbitals in Gaussian/GAMESS log file

After calculating the energy of a $\ce{CH4}$ molecule with a 6-31G(d,p) basis set, I obtained the Gaussian/GAMESS log file and describe a part of the log file as follows. ...
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8 votes
2 answers
131 views

Geometrical Optimization not converging for a double perovskite quantum dot, using Gaussian

I am trying to optimize the geometry of a Cs4CuSb2Cl12 Stoichiometric Quantum dot and I have checked the input multiple times, but the opt+freq calculation is not converging. The quantum dot has about ...
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5 votes
1 answer
179 views

Calculated Redoxpotential is too far away from experimental value

I calculated the redox potential with Gaussian for hydroquinone with different combinations of functional/basis sets always values like 5.4V (B3LYP/6-311G+(2d,p) and SMD model). The experimental value ...
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5 votes
1 answer
106 views

How to alter the charge and multiplicity of a molecule in Gaussian?

I want to perform redox potential calculations using the Gaussian. To check if I'm setting things up correctly, I want to compare it to a benchmark database published by Grimme et al.[1] I performed ...
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7 votes
1 answer
84 views

Symmetry group of p-benzoquinone

I am trying to calculate the UV-visible spectrum of p-benzoquinone. In the literature, the point group of p-benzoquinone is $D_{2h}$, but when I optimize this molecule in the ground state with ...
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6 votes
1 answer
86 views

Transforming basis functions from Cartesian to speherical

I read the basis set from book A d-type GTO written in terms of the spherical functions has five components (Y2,2, Y2,1, Y2,0, Y2,1, Y2,2),but there appear to be six components in the Cartesian ...
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5 votes
2 answers
228 views

The format and values provided by Basis Set Exchange

In this question and answers, I found that Basis Set Exchange provides information about the orbitals (e.g., the orbital exponents and contraction coefficients). For example, the following example is ...
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10 votes
4 answers
835 views

How can I find the parameters in a basis set?

I have a question about the basis functions of Gaussian. When the basis function is set (e.g., 6-31G), I would like to know the specific value of Gaussian's parameters for each atom. In particular, I ...
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9 votes
2 answers
317 views

Calculating the excited state dipole moment

I am trying to calculate the dipole moment of an excited state, using "Gaussian" software. My input commands were: ...
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7 votes
2 answers
482 views

Does QC convergence mode in Gaussian make a difference?

I have been using Gaussian16 por metal complexes SCF single-point calculations involving triplets to investigate phosphorescence. I have actually run into trouble (very long computational time, even ...
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7 votes
1 answer
74 views

Frequency error in Gaussian CASSCF(10,10)

I am stuck in calculating the frequencies of one optimised geometry for naphthalene CASSCF(10,10) with Gaussian 16. I have optimised its geometry and checked the active space is the pi system of it, ...
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4 votes
0 answers
65 views

Gaussian warning [closed]

I am running an ONIOM optimization calculation on GAUSSIAN software and when I open the LOG file I get a warnig saying: ...
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  • 517
6 votes
2 answers
359 views

Geometry optimization with Moller-Plesset MP4

Can we optimize a molecular structure using Moller-Plesset MP4 method on GAUSSIAN software? If yes what keyword do we have to add?
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13 votes
1 answer
601 views

How to plot a Gaussian cube file with python/matplotlib?

I know there are programs that can automatically visualize .cube files (like VMD), but I'm trying to do it myself in python/matplotlib (or equivalent) to better understand what the numbers mean. I ...
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9 votes
1 answer
242 views

How to eliminate imaginary frequencies during a Gaussian geometry optimization?

When conducting a minimization on Gaussian software, What are the procedures used to eliminate imaginary frequencies if we have already found a stationary point? Are there any keywords that would help ...
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  • 517
8 votes
1 answer
292 views

How to generate a input file for gaussian in Avogadro 2? [duplicate]

I made auto optimization working by installing openbabel using sudo apt install openbabel. Is there any way to make Gaussian extension working by doing something? I'...
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13 votes
3 answers
244 views

Quantum chemistry in external electrostatic field?

Which quantum chemistry methods can be used in an external electrostatic field? Also which software supports that? I'm interested in anything from semiempirical (eg XTB) to DFT (eg ωB97, B3LYP-D3) ...
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  • 385
8 votes
0 answers
63 views

Visualizing wavefunctions in real space [closed]

I would like to generate wavefunctions as functions of spatial coordinates (X, Y, Z) using Gaussian G09 and then visualize them. How might I go about doing this? I am using Linux and my preferred ...
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8 votes
0 answers
91 views

How to compare the stability of two nano-structures using ab-inito calculations? [closed]

I have recently started working on Double Perovskites Quantum Dots and one of the main issue with them is that they are not much stable. Some papers did talk about how much stable there compounds are ...
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6 votes
0 answers
103 views

How to calculate energy gradient and Hessian with respect to only a few internal coordinates using Gaussian? [closed]

I would like to form the (numerical) gradient and the Hessian of the total electronic energy with respect only to a few internal coordinates (namely, the six intermolecular coordinates of a weakly ...
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