[gmx-users] electric fields

[David van der Spoel]

On 2015-02-15 20:49, mah maz wrote:
> Dear Justin, David
>
> Thank you for your reply.
> I have also seen not implemented yet as Justin said.
> David, I hope your option E-xt works. But still I don't know if I should
> supply its parameters the same as E-x or it would be different.
The field has the form of a gaussian laser pulse

E(t) = E0 exp ( -(t-t0)^2/(2 sigma^2) ) cos(omega (t-t0))

the four parameters are set like
E-x  = 1 E0 0
E-xt = omega t0 sigma

In the special case that sigma = 0 the exponential term is disregarded 
and only the cosine term is used.

More details in Carl Caleman and David van der Spoel: Picosecond Melting 
of Ice by an Infrared Laser Pulse - A Simulation Study Angew. Chem. 
Intl. Ed. 47 pp. 1417-1420 (2008)


>
> Thanks a lot!
>
> On Sun, Feb 15, 2015 at 9:01 PM, mah maz <mahmaz71 at gmail.com> wrote:
>
>> Hi all,
>> I need to apply magnetic and also alternating electric field to my system,
>> but I can't find any options. Can anyone help me?
>> thanks!
>>
>> On Fri, Feb 13, 2015 at 8:44 PM, mah maz <mahmaz71 at gmail.com> wrote:
>>
>>> Dear all,
>>> What kinds of electric and magnetic fields are available in gromacs? Are
>>> there any commands for discontinuous(alternating) fields?
>>> thank you!
>>>
>>
>>


-- 
David van der Spoel, Ph.D., Professor of Biology
Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205.
spoel at xray.bmc.uu.se    http://folding.bmc.uu.se