Re: gamma in langevin thermostat ver 3.3.1

[Alexander Afanasyev]

Thanks you for the answer. 

Does anyone know what gamma is in Espresso 3.3.1?

> On Nov 11, 2019, at 4:32 AM, Rudolf Weeber <address@hidden> wrote:
> 
> Hi Alex,
> On Sun, Nov 10, 2019 at 03:42:56PM -0500, Alexander Afanasyev wrote:
>> I am using a langevin thermostat in ver 3.3.1. I am confused what gamma is 
>> (a friction coefficient or collision frequency)?
>> I remember someone answered this question two years ago, but it is still 
>> unclear if it was fixed in ver 3.3.1.
> First of all, support for the TCL version has been terminated. It is strongly 
> recommended to use Espresso 4.1 for all current work.
> In current versions of Espresso, gamma is the friction coefficient in the 
> Langevin eqn:
> m x.. -gamma x. +F_random +F =0
> 
> However, this was different at some point. IIRc, gamma included some mass 
> dependence. I do not know when this changed.
> 
> Regards, Rudolf
>