VMD-L Mailing List

From: Joel Subach (mjsubach_at_alumni.ncsu.edu)
Date: Wed May 08 2024 - 14:06:02 CDT

..feel free to comment on my suggested solvation modifications below (I am
unsure if its formatted correctly and moreover if there are any suggested
modifications needed i.e. -D3 etc.), thanks:):

Geometry Optimization: ! MP2 6-31G* TightSCF opt -->

! B3LYP 6-31G* TightSCF opt
!CPCM(Water)
%maxcore 4000

%output
  PrintLevel Mini
  Print [ P_Mulliken ] 1
  Print [ P_AtCharges_M ] 1
end

%coords
  CTyp xyz
  Charge 0
  Mult 1
  Units Angs
  coords

N 111.38200378 109.63400269 61.88000107
N 105.40599823 107.05400085 60.49200058
..
H 101.45600128 102.40799713 61.65399933
H 109.52500153 102.40299988 59.88899994
  end
end

Water Interaction: ! HF 6-31G* TightSCF opt --->

! B3LYP 6-31G* TightSCF opt
!CPCM(Water)
%maxcore 1000

%geom
 ConnectFragments
   { 1 2 O 9 66 }
 end
 Constraints
   { B 9 66 C }
   { D * 67 9 * C }
    end
  invertConstraints true
end

%coords
  CTyp xyz
  Charge 0
  Mult 1
  Units Angs
  coords

N(1) 111.3489990234375 110.1510009765625 61.86199951171875
N(1) 106.43699645996094 106.68199920654297 61.29399871826172
..
O(2) 108.47699737548828 112.79299926757812 61.159000396728516
H(2) 108.85800170898438 112.92400360107422 62.027000427246094
  end
end

Calc. Bonded: ! MP2 6-31G* TightSCF opt NumFreq --->

! B3LYP 6-31G* TightSCF opt NumFreq
!CPCM(Water)
%maxcore 1000

%geom
 ConnectFragments
   { 1 2 O 9 66 }
 end
 Constraints
   { B 9 66 C }
   { D * 67 9 * C }
    end
  invertConstraints true
end

%coords
  CTyp xyz
  Charge 0
  Mult 1
  Units Angs
  coords

N(1) 111.3489990234375 110.1510009765625 61.86199951171875
N(1) 106.43699645996094 106.68199920654297 61.29399871826172
..
O(2) 108.47699737548828 112.79299926757812 61.159000396728516
H(2) 108.85800170898438 112.92400360107422 62.027000427246094
  end
end

On Tue, May 7, 2024 at 8:33 PM Joel Subach <mjsubach_at_alumni.ncsu.edu> wrote:

> Hello VMD Community:),
>
> I wish to add an Implicit Solvation to my suggested CHARMM prerequisite
> compatible ffTK ORCA Methods outlined below:
>
> Geometry Optimization: ! MP2 6-31G* TightSCF opt
>
> Water Interaction: ! HF 6-31G* TightSCF opt
>
> Calc. Bonded: ! MP2 6-31G* TightSCF opt NumFreq
>
> Only experts have been recommended to modify the above ffTK suggested
> methods since the HF/6-31G(d) level of theory needs to be maintained
> towards consistency with the CHARMM force field. After reading the ORCA
> Manual Implicit Solvation Section I still find this modification towards
> implicit solvation to be beyond the scope of my expertise for best results.
> Accordingly if you have any suggestion towards modifying my above input
> files towards ORCA execution to generate best solvent exposed calculations
> that would yet still be CHARMM compatible to their above methods feel free
> to make a suggestion(s) . (The ffTK literature and tutorial do not exhibit
> this expertise.). Thanks if you know:).
>
> Joel[image: 🚀]
>