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<p>Yup, that should be physically sound.</p>
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<p>Alex</p>
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<p><span class=rvts7>Dear Alex,</span></p>
<p><span class=rvts7>I have another question related to coulombtype selection. I dont want to use pbc in my system so, PME and Ewald are not good choices. If I use Reaction-field-zero and define a rcoulomb equal to my system size ( since epsilon-rf is 0 out of cutoff size) would it do the same work as finding epsilon-rf in generalized field reaction?</span></p>
<p><span class=rvts7>THANKS!</span></p>
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<p><span class=rvts7>On Tue, Apr 28, 2015 at 10:22 PM, Maryam Kowsar <</span><a class=rvts8 href="mailto:maryam.kowsar@gmail.com">maryam.kowsar@gmail.com</a><span class=rvts7>> wrote:</span></p>
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<p><span class=rvts7>If I use PME there's no need to find epsilon-rf, but I have to change some other parameters. I will try it.</span></p>
<p><span class=rvts7>Thank you very much Alex! </span></p>
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<p><span class=rvts7>On Tue, Apr 28, 2015 at 11:31 AM, Alex <</span><a class=rvts8 href="mailto:nedomacho@gmail.com">nedomacho@gmail.com</a><span class=rvts7>> wrote:</span></p>
<p><span class=rvts7>With reaction-field-zero, the only option is epsilon-rf=0. That aside, if the nanotube is small, i would use cut-off electrostatics with coulomb-cutoff comparable to the length of the tube.</span></p>
<p><span class=rvts7>If the tube is long, I would use standard pme. I would be extremely careful about using truncated electrostatics in general. Given the above, I am not sure I understand what's there to calculate, unless you mean running a simulation and _obtaining_ a dielectric property as a result. In that case, given you system, it is a completely different discussion.</span></p>
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<p><span class=rvts7>Alex </span></p>
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<p><span class=rvts7>MK> Not a poorly formed but a general question! </span></p>
<p><span class=rvts7>MK> You are right about reaction-field-zero. reaction-field leads to</span></p>
<p><span class=rvts7>MK> bad energy conservations. So, I decided to use reaction-field-zero</span></p>
<p><span class=rvts7>MK> but as I have some charges I don't know what to do with them. I</span></p>
<p><span class=rvts7>MK> have a CNT in which there are some ions. I want to calculate the</span></p>
<p><span class=rvts7>MK> epsilon-rf for it. I don't know if epsilon-rf belongs to the whole</span></p>
<p><span class=rvts7>MK> system and if so, how I should calculate it. </span></p>
<p><span class=rvts7>MK> thanks!</span></p>
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<p><span class=rvts7>MK> On Tue, Apr 28, 2015 at 10:50 AM, Alex <</span><a class=rvts8 href="mailto:nedomacho@gmail.com">nedomacho@gmail.com</a><span class=rvts7>> wrote:</span></p>
<p><span class=rvts7>MK> That's a pretty poorly formed question, including the part where you</span></p>
<p><span class=rvts7>MK> actually "calculate" the epsilon-rf value. Can you please try again with</span></p>
<p><span class=rvts7>MK> a description of your system?</span></p>
<p><br></p>
<p><span class=rvts7>MK> Alex</span></p>
<p><br></p>
<p><span class=rvts7>MK>> Dear all,</span></p>
<p><span class=rvts7>MK>> I use reaction-field-zero as the coulombtype for my system. I wonder how I</span></p>
<p><span class=rvts7>MK>> should choose the right epsilon-rf. How can I calculate the dielectric</span></p>
<p><span class=rvts7>MK>> constant in the system?</span></p>
<p><span class=rvts7>MK>> Thank you.</span></p>
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<p><span class=rvts9>-- </span></p>
<p><span class=rvts9>Best regards,</span></p>
<p><span class=rvts9> Alex </span><a class=rvts8 href="mailto:nedomacho@gmail.com">mailto:nedomacho@gmail.com</a></p>
<p><span class=rvts9>--</span></p>
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<p><span class=rvts10>-- </span></p>
<p><span class=rvts10>Best regards,</span></p>
<p><span class=rvts10> Alex </span><a class=rvts11 href="mailto:nedomacho@gmail.com">mailto:nedomacho@gmail.com</a></p>
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