[Pw_forum] one more question about NEB and CP

[Nicola Marzari]

vega lew wrote:
> Dear all,
>
> I used to perform NEB calculations to estimate the energy barrier for 
> certain chemical reaction.
> The calculated activation barrier is about 0.2 eV. I want the see the 
> reaction process during some pico-second of CP calculations.
> Do you think the reaction could happen in such a short time?  and what 
> temperature is suitable for jumping over the saddle point?
>
> thank you for reading
>
> best wishes,
>
> vega


Hi Vega,

try to work this out by yourself, looking at the arrhenius formula ; put an
attempt rate comparable to say an optical phonon. But the answer is 
probably yes,
especially if you are a bit over room temperature (500-600K).

                nicola


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