Thank you very much for kind advices. Here is some warning, and I don't know whether there would be some problem or not: ; 'fake' gromacs topology generated from topotools. ; WARNING| the purpose of this topology is to allow using the&nbsp; |WARNING ; WARNING| analysis tools from gromacs for non gromacs data.&nbsp;&nbsp; |WARNING ; WARNING| it cannot be used for a simulation.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |WARNING <div></div> <pre> At&nbsp;2011-05-30，"Francesco&nbsp;Oteri"&nbsp;&lt;francesco.oteri@gmail.com&gt;&nbsp;wrote:

&gt;Il&nbsp;29/05/2011&nbsp;21:58,&nbsp;albert&nbsp;ha&nbsp;scritto:

&gt;&gt;&nbsp;Hello:

&gt;&gt;&nbsp;I&nbsp;am&nbsp;wondering,&nbsp;is&nbsp;it&nbsp;possible&nbsp;to&nbsp;convert&nbsp;NAMD&nbsp;topol&nbsp;psf&nbsp;file&nbsp;into&nbsp;

&gt;&gt;&nbsp;Gromacs&nbsp;topol&nbsp;format?

&gt;&gt;

&gt;&gt;&nbsp;Thank&nbsp;you&nbsp;very&nbsp;much

&gt;

&gt;Hi&nbsp;albert,

&gt;you&nbsp;can&nbsp;try&nbsp;with&nbsp;the&nbsp;following&nbsp;commands:

&gt;

&gt;vmd&nbsp;.psf&nbsp;.pdb

&gt;topo&nbsp;writegmxtop&nbsp;output.top

&gt;

&gt;I&nbsp;recently&nbsp;tried&nbsp;with&nbsp;vmd1.9

&gt;

&gt;--&nbsp;

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