<span>On 25/05/11, <b class="name">sreelakshmi ramesh </b> <sree.lakshmi@research.iiit.ac.in> wrote:</span><blockquote cite="mid:BANLkTi=j4DtJOodyAU+aOjjDbhjh+kexdQ@mail.gmail.com" class="iwcQuote" style="border-left: 1px solid rgb(0, 0, 255); padding-left: 13px; margin-left: 0pt;" type="cite"><div class="mimepart text html">Hai all,<br /> My system is just a water Spc model. <br /> I am trying to create a table.xvg which would deal with nonbonded intearction for water-water for say SPC model.<br /><br />If i have to calculate the potential i have to consider the interaction between <br />
1.O of water1--O of water 2(LJ+COLOUMB) [CREATED A TABLE that containsr, f (r), −f (r), g(r),−g (r), h(r) and −h (r) ]<br />2.H of water 1--O of water 2(COLOUMB) [ are tables needed ?]<br />3.H of water 1--H of water 2(COLOUMB) [are tables needed ?]</div></blockquote><br />That depends whether you're trying to apply a different or the same functional form to the interactions of the hydrogen atoms, i.e. whether you have an energy group for the whole system, or have O and H in different energy groups so that you can apply different functional forms to different interactions.<br /> <br /><blockquote cite="mid:BANLkTi=j4DtJOodyAU+aOjjDbhjh+kexdQ@mail.gmail.com" class="iwcQuote" style="border-left: 1px solid rgb(0, 0, 255); padding-left: 13px; margin-left: 0pt;" type="cite"><div class="mimepart text html">for 2 and 3rd case should i create 2 tables respectively ? if not how is the potential is calculated for the the last two cases ?</div></blockquote><br />The user table applies to all interactions unless you start playing around with energygrp_table. So your hydrogen interactions use the table, but only look up the values for f.<br /><br /><blockquote cite="mid:BANLkTi=j4DtJOodyAU+aOjjDbhjh+kexdQ@mail.gmail.com" class="iwcQuote" style="border-left: 1px solid rgb(0, 0, 255); padding-left: 13px; margin-left: 0pt;" type="cite"><div class="mimepart text html">and if it has to be to created since the lennard jones part say g(r),−g (r), h(r) and −h (r) is zero for all values of r should i just create a table with r,f(r)and -f'(r) for last two cases?</div></blockquote><br />6.7.2 covers this last point.<br /><div class="mimepart text html"><br />Mark<br />
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