Re: gradual heating problem

Date: Sun May 08 2016 - 11:21:13 CDT

Thanks Brian
                       I solved the problem, i was initializing velocity by temperature using reinitvels command but i was using first time step as last time step of minimization. Setting first time step as 0 solved the problem.
However as you said you dont heat below 250 k, so do you heat your system before equilibration and after minimization. 250 and 310 k are not that different. If i am not heating below 250, do i have to heat my system at all if i want to do my simulation at 310K.


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> On May 8, 2016, at 11:04 AM, Brian Radak <> wrote:
> How did you initialize velocities? The thermostat does not control initial conditions.
> Also, it's very hard to hold most systems at such low temperature - normal dynamics should repartition potential energy into kinetic energy very quickly.
> I stopped heating from temperatures below 250 K or so a long time ago because the system would often naturally heat up faster than my increment (it's hard to say if your choice of 100 steps will overcome this). I generally only use these kinds of protocols for annealing up to 600 K or so and then ramping down the temperature afterward.
> HTH,
> Brian
>> On 05/08/2016 10:27 AM, Dhiraj Srivastava wrote:
>> Hi
>> I am trying to gradually heat my system after minimization and using the following set of commands.
>> reassignFreq 100
>> reassignTemp 5
>> reassignIncr 5
>> reassignHold 310
>> no where else in the entire configuration file i can see number 310. however after starting the calculation, system is going right away to 310 kelvin. I looked at previous post but could not find satisfactory answer. How can I resolved this issue?
>> Thanks
>> Dhiraj
> --
> Brian Radak
> Postdoctoral Appointee
> Leadership Computing Facility
> Argonne National Laboratory
> 9700 South Cass Avenue, Bldg. 240
> Argonne, IL 60439-4854
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