Also, if you simulate ions, there can be a noticeable polarization
effect, depending on the particular simulated species.
> On Sat, Nov 12, 2011 at 1:22 PM, Ismail, Mohd F. <farid.ou.edu> wrote:
>> I am trying to simulate ions in bulk organic solvent. I use gaff for internal parameters. For charges, if I use bcc at first, but the density would not converge. When I use RED, the density is still about 3% higher.
>>
>> Will it be alright if I use higher method or basis set to calculate the charges? I saw some documentation that gaff and amber use HF with 6-31g* for the parameters and charges.
>>
>> I also check the trajectory, but there seems to be no 'stupid' conformation.
>
> The charges are always very sensitive to the ab initio method applied.
> Try MP2 instead, for example. BTW, 3% higher density is not so much
> terrible for most tasks.
>
>
> Dr. Vitaly V. Chaban, 430 Hutchison Hall, Chem. Dept.
> Univ. Rochester, Rochester, New York 14627-0216
> THE UNITED STATES OF AMERICA
>
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Received on Sun Nov 13 2011 - 13:00:06 PST
