Can any body help me for NICS, NICSiso, NICS(1), NICSpizz, NICSzz,NICS(1)zz, LMO-NICS and CMO-NICS calculations with gauss view 5.0.8 or any other way?
Actually, I need to calculate NICS for pi and Sigma separately.
What caution need to calculate these for non planner molecules?
The simplest way to get started is simply to add a ghost atom (I believe this is Bq in Gaussian syntax) to your system, then run an NMR calculation. The NICS parameter is then the shielding for the ghost atom (but with the opposite sign).
The placement of the ghost atom is a difficult question. For a planar ring, NICS0 would be the centre of the ring. NICS1 would be 1 angstrom perpendicularly above the ring centre. It is probably worth doing a literature search to see what others have done for calculating NICS in non-planar systems.
When looking for a straightforward tutorial I stumbled across this document:
http://www.academia.edu/3406598/How_to_calculate_NICS_Nucleus_Independent_Chemical_Shift_A_general_guide_for_beginners_some_notes_for_experts
Maybe it is of interest for you.
Cheers,
Paul
http://www.academia.edu/3406598/How_to_calculate_NICS_Nucleus_Independent_Chemical_Shift_A_general_guide_for_beginners_some_notes_for_experts
Thank you for your kind answer @ Grant Hill but what are the meaning and difference of NICS(0) NICS(1) NICS(0)zz, NICS(1)zz, NICS(min)zz, NICS(0)pzz, NICS(1)pzz, NICS(2)pzz? [p=pi]
Thank you for your kind reply @ Paul Jerabek, but I already notice it.
Thank you once again for both of you for valuable replies .
I covered NICS(0) and NICS(1) in my answer, but the rest I'm not sure about. Perhaps they need IGLO (localised orbital) methods, I'm not sure they are available in Gaussian.
There is another method for calculation of the aromaticity via a statistical model for benzene or non-benzene molecules such as B3N3H6 or.....
In this method , a statistical computing of nucleus-independent chemical shifts (S-NICS) has been done in viewpoin of probes or ghost atom motions in a sphere of shielding and deshielding spaces of molecular rings.
By generation of pseudo-random numbers in a Monte Carlo calculation which are distributed in various functions, the maximum abundant of skew and asymmetry parameters have been calculated for (η*), (κ*), . Finally the modified isotropy has been calculated for benzene, borazine, naphthalene and BnNnHx(n=15,16) as an the aromaticity criterion.
The advantage of this model is because it can be used for all molecular rings and the disadvantage of this model is taking time comparing to the previous methods
For any further details please look at to the reference as follows:
Monajjemi,M.; Nayyer T. Mohammadian J. Comput. Theor. Nanosci. (S-NICS): an Aromaticity criterion for Nano molecules 2015, 12, 4895-4914
Hello Mehdi
I hope everything is going well with you. Based on my knowledge, Multiwfn program can calculate aromaticity of non-planar systems by NICS method. It can also calculate aromaticity values based on HOMA, FLU, PDI, and etc methods. It is free of charge.Please follow the link bellow and download it:
https://multiwfn.codeplex.com/
Good luck
Mehdi
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