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<p>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.</p>
<p>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.</p>
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<p>Alex </p>
<p><br></p>
<p><span class=rvts11>MK> Not a poorly formed but a general question! </span></p>
<p><span class=rvts11>MK> You are right about reaction-field-zero. reaction-field leads to</span></p>
<p><span class=rvts11>MK> bad energy conservations. So, I decided to use reaction-field-zero</span></p>
<p><span class=rvts11>MK> but as I have some charges I don't know what to do with them. I</span></p>
<p><span class=rvts11>MK> have a CNT in which there are some ions. I want to calculate the</span></p>
<p><span class=rvts11>MK> epsilon-rf for it. I don't know if epsilon-rf belongs to the whole</span></p>
<p><span class=rvts11>MK> system and if so, how I should calculate it. </span></p>
<p><span class=rvts11>MK> thanks!</span></p>
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<p><span class=rvts11>MK> On Tue, Apr 28, 2015 at 10:50 AM, Alex <</span><a class=rvts12 href="mailto:nedomacho@gmail.com">nedomacho@gmail.com</a><span class=rvts13>> wrote:</span></p>
<p><span class=rvts11>MK> That's a pretty poorly formed question, including the part where you</span></p>
<p><span class=rvts11>MK> actually "calculate" the epsilon-rf value. Can you please try again with</span></p>
<p><span class=rvts11>MK> a description of your system?</span></p>
<p><br></p>
<p><span class=rvts11>MK> Alex</span></p>
<p><br></p>
<p><span class=rvts14>MK>> Dear all,</span></p>
<p><span class=rvts14>MK>> I use reaction-field-zero as the coulombtype for my system. I wonder how I</span></p>
<p><span class=rvts14>MK>> should choose the right epsilon-rf. How can I calculate the dielectric</span></p>
<p><span class=rvts14>MK>> constant in the system?</span></p>
<p><span class=rvts14>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=rvts10 href="mailto:nedomacho@gmail.com">mailto:nedomacho@gmail.com</a></p>
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