Re: [ESPResSo-users] Reason for warm up integration

[Peter Košovan]

Because as soon as you get rid of the overlaps, the integration of the equations of motion becomes numerically stable. And a stable integration reproduces the correct physics of particle collision, as you described it. By pure thermal fluctuations, the particles never come closer than 0.9*sigma (you use the standard LJ potential). More precisely, the probability that this happens during the simlation is negligible.

inter ljforcecap 0 switches off the capping and uses the full potential (please read the manual).

With best regards,

peter

On Tue, Sep 1, 2015 at 5:36 PM, Nairhita Samanta <address@hidden> wrote:

Hello all!

            I am trying to understand the basic structure of the Espresso simulations as I am completely new in this field.  I understand why we need capping, without which the system will blow up. But I wanted to know why do we increase capping to a certain extent and then make it zero in the end? Is it because the particles will avoid coming to each other if the energy capping keeps on increasing and potential energy will increase as a consequence. Then why we make it zero in the end?

Regards,

Nairhita

--

Dr. Peter Košovan

Department of Physical and Macromolecular Chemistry

Faculty of Science, Charles University in Prague, Czech Republic

Katedra fyzikální a makromolekulární chemie

Přírodovědecká fakulta Univerzity Karlovy v Praze

www.natur.cuni.cz/chemistry/fyzchem/
Tel. +420221951290

Fax +420224919752

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