[Pw_forum] one more question about NEB and CP

lfhuang lfhuang at theory.issp.ac.cn
Mon Nov 23 09:30:18 CET 2009


(Because of the mistake I made due to not knowing the limitation of the size of the attachement, the previous emails are not complete. Now, the below one is complete.) 
 
Dear Vega Lew: 
From the reaction rate theory, you can estimate with the Arrhenius equation, with your activation energy value (0.2eV), I have made an estimation for you (please see the attachment). From my estimation, if you want to the reaction to occur within several pico-seconds, the temperature should be above about 1000 Kelvin (reaction time is proportional to the inverse of the reaction/jump frequency). (if the Zero point energy correction can not omitted, please add it in to the activation energy: E_ac=delta_E_p - E_ZPE). 
Best Wishes! 
Yours Sincerely 
L.F.Huang 
> 
> Message: 1 
> Date: Sun, 22 Nov 2009 23:16:34 -0800 
> From: vega lew 
> Subject: [Pw_forum] one more question about NEB and CP 
> To: PWSCF Forum 
> Message-ID: 
> 
> Content-Type: text/plain; charset="iso-8859-1" 
> 
> 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 
> 
> -- 
> ================================================================================== 
> Vega Lew ( weijia liu) 
> Graduate student 
> State Key Laboratory of Materials-oriented Chemical Engineering 
> College of Chemistry and Chemical Engineering 
> Nanjing University of Technology, 210009, Nanjing, Jiangsu, China 
> ****************************************************************************************************************** 
> Email: vegalew at gmail.com 
> Office: Room A705, Technical Innovation Building, Xinmofan Road 5#, Nanjing, 
> Jiangsu, China 
> 
------ 
====================================================================== 
L.F.Huang(黄良锋) ph.D candidate, DFT and phonon physics 
====================================================================== 
Add: Research Laboratory for Computational Materials Sciences, 
Instutue of Solid State Physics,the Chinese Academy of Sciences, 
P.O.Box 1129, Hefei 230031, P.R.China 
Tel: 86-551-5591464-328(office) 
Fax: 86-551-5591434 
Web: http://theory.issp.ac.cn</a> (website of our theory group) 
http://www.issp.ac.cn</a> (website of our institute) 
====================================================================== 


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