[gmx-users] fourier spacing

[Erik Lindahl]

Rui Qiao wrote:
> Dear all:
> 	In my simulation, the interesting physics happens only in y
> direction, does this means that I can use a coarse fourier spacing in z
> and x diraction and only have fine grid in y direction?
> 
> 	sincerely,
> 
> 	Rui

Hm.. Interesting idea ;-)

The conservative answer is probably no; even i your y forces will be 
correct the x & z forces might be off and affect your results.

In practice I would probably check it, though :-) Run through a small 
simulation and compare the x,y & z forces for different spacings. As far 
as I can tall, the only problem that could happen is strange forces (and 
thus pressure) in x & z directions, but I won't swear by it :-)

Cheers,

Erik