Calculate dynamic structure factor

Hi again,

15.10.2013, 06:10, "Aiqun Huang" <[email protected]>:

Hi Oleg,

Thanks for replying. I read the first several pages of the paper you referred. If I understand right, what you meant is calculate the dynamic structure factor Eq. 4 from Eq. 1.

What I meant is to calculate Eq. 4 (and I calculated S(k,w) too), where rho_k(t) is the expression on top of the p. 7777.

You said that
" Dynamic structure factor can be represented as a temporal Fourier transform of an intermediate scattering function, which, in turn, needs for its calculation only one complex number for each moment of time"

can you give more details on that?

Again, to calculate F(k,t) - eq. 4 - you don't need all the particle coordinates, but only rho_k(t) for each timestep and each k. So instead of preserving all the trajectory, you read it from disk, only store rho_k(t) for each timestep and may then calculate F(k,t) or S(k,w).

I am indeed interested in how you exactly implemented the calculation into code, if possible,
it will be great to read your code even you think it was poorly written.

Ok, attached. It was written to calculate DSF for LJ liquid, but maybe some parts may be useful for you.

Regards,
Oleg.

spectrum.tar.gz (23.9 KB)