How do I fix radical anion on a particular molecule of a dimer using Gaussian 09?

My molecule of interest is a single negatively charged glucose-based molecule that consists of 30 atoms (9 carbon atoms, 8 oxygen atoms and 13 hydrogen atoms). The total valence electrons are 131 with -1 charge. Therefore, I have set -1 charge and a multiplicity of 2 (since it has one unpaired electron) in the input file. However, I faced an error termination that stated this "The combination of multiplicity 2 and 132 electrons is impossible". I have no idea of how the Gaussian09 program calculated a total of 132 electrons. When I changed the setting to 0 charge and a multiplicity of 2, the calculation works fine (Gaussian calculated 131 electrons) with a normal termination. Is there anyone can give some inputs on this? Thank you.

Can you anybody tell me, what will be the value of charge and multiplicity of radical cation and dehydrogenated radical cation for the calculation in Gaussian?

During optimization PCM (IEFPCM) solvent calculations of a molecule whose geometry was previously optimized in the gas phase, the error on total polarizations charges repeatedly came up in the output file. The calculations are being performed at the B3LYP/6-31G(d) level of theory, with the software Gaussian 16. Can someone give suggestions on how to overcome this error?

How to specify the position of a radical (in an organic molecule) in the input file during geom opt or SP calculation using Gaussian 09?

Hello

I am working on the calculation of metathesis reaction bath between Grubbs-Hoveyda catalyst and ethene as an olefin model by using gaussian 09 for this purpose,

every time when I calculate TS with Berny ts approach in GS I got the started geometry.

So, I ask about the exact procedure to obtain the correct transition state structures including the correct energy and geometry with one imaginary frequency.

And how to construct the energy profile ??

kindly, I need correct input/output files to guide me.

note: I attached some files as examples,

Thanks in advance..

I found some where that, The ionization potential (IP) and electron affinity (EA) for the ground state configuration can be computed using:

IP=E(cation) - E(neutra) and EA= E(neutral) - E(anion)

But I dont know how to calculate the E(cation) and E(neutral) using GAUSSIAN 09 code. I need your Help. The E(neutral) i considered is the one I obtain after the geometry optimization of my molecule, do I have reason to considered it like E(neutral)???

some one told me that I have to add or remove one electron on the neutral form of my molecule and perform a single point calculation on each in other to have E(anion) and E(cation)  respectivelly but I don't know how to modifiered the number of electron in gaussian. I need help.

Hello everyone,

I deal with the calculations of QM charges for protein fragments. Each fragment consists of aproximately 250 non-hydrogens atoms.

Currently I started these calculation using B3LYP theory level, NPA distribution scheme and 6-31G* basis set.

I ran these calculations for 41 fragments. However, only 20 of them ended with the 'Normal termination'. The remaining 20 fragments ended with this error message:

>>>>>>>>>> Convergence criterion not met.

SCF Done: E(RB3LYP) = -14532.8135584 A.U. after 129 cycles

NFock=128 Conv=0.48D-03 -V/T= 2.0071

Convergence failure -- run terminated.

Error termination via Lnk1e in /afs/ics.muni.cz/software/g09-D01/em64t.sse4.2/g09/l502.exe at Sat Mar 28 13:01:44 2015.

Do you have any idea how to solve this problem?

Hi all,

I have a compound with a particular functional group surrounded by water molecules. I am using Gaussian G09 to optimise, first with HF/6-31+g** and then I will progressively move higher per stable structure. Unfortunately, of the twenty different model arrangements (4 functional groups I am interested in and 8, 10, 12, 14, 16) water molecules neighbouring) only three of the twenty ran successfully. The others suffered from the following error (atom numbers will have been different obviously):

GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad

Berny optimization.

Using GEDIIS/GDIIS optimizer.

Bend failed for angle    39 -    70 -    68

Tors failed for dihedral    15 -    39 -    70 -    68

Tors failed for dihedral    51 -    39 -    70 -    68

Tors failed for dihedral    69 -    68 -    70 -    39

FormBX had a problem.

Error termination via Lnk1e in /usr/local/g09_d01/l103.exe at Tue Mar 24 10:12:24 2015.

When I investigate this further, the first failure (Bend on the angle 39, 70, 68) is an angle between the oxygen and hydrogen of a water, followed by the hydrogen of a hydroxyl group. It turns out to be exactly 180 degrees. I understand the optimisation algorithm in gaussian struggles with inline angle. 

Surely, restarting with a different arrangement to the water molecules isn't the best or only solution? Any tips or suggestions are very grateful.

Thanks

Anthony

One of my coordination compounds calculations had the following error in Gaussian 09. Error termination in NtrErr: NtrErr Called from FileIO. Does anyone have an idea how it can be resolved?