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> Dear GROMACS developers,<BR>
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> In order to measure the glass transition temperature of water and aqueous solutions with different cooling rates, Stanley et al have reported a modified NVT simulation - Physical Review Letters 93, 2004 047801-1.<BR>
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>His method is as follows:<BR>
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>The simulation is run in the NVT ensemble. The temperature during the simulation, ref_T, is controlled by using a Berendsen thermostat .<BR>
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>In a standard NVT simulation, To is constant. In their cooling/heating simulations, Berendsen thermostat is used but, at everytime step, they also update the bath temperature ref_T such that<BR>
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>ref_T= ref_T - deltaT, with deltaT= cooling/heating rate * timestep.<BR>
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>This is done at every time step before rescaling the velocities.<BR>
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>In my case, I want to employ a cooling rate of -3*10^10 K/fs and time step is 1 fs.<BR>
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>that is delta T is -0.00003K/fs<BR>
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>and ref_T has to be updated at everytime step using the equation,<BR>
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>ref_T= ref_T - 0.00003 -----------> eq.1<BR>
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>How can I do this in GROMACS 3.3.3?<BR>
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>I mean which file should I modify before compiling again;<BR>
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>I checked md.c, do_gt.c and coupling.c in 3.3.3/src/kernel but got confused as to find the line where I could impliment eq.1.<BR>
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>I really hope that any of you can help me in this regard.<BR>
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>regards,<BR>
>Jes<BR>
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