Static_structure_factor Liquid

structure of classical monatomic liquid. atoms have many nearest neighbors in contact, yet no long-range order present.

in liquid, atoms not form crystalline lattice, nor show other form of long-range order. evidenced absence of bragg peaks in x-ray , neutron diffraction. under normal conditions, diffraction pattern has circular symmetry, expressing isotropy of liquid. in radial direction, diffraction intensity smoothly oscillates. described static structure factor s(q), wavenumber q=(4π/λ)sinθ given wavelength λ of probe (photon or neutron) , bragg angle θ. oscillations of s(q) express near order of liquid, i.e. correlations between atom , few shells of nearest, second nearest, ... neighbors.

a more intuitive description of these correlations given radial distribution function g(r), fourier transform of s(q). represents spatial average of temporal snapshot of pair correlations in liquid.

radial distribution function of lennard-jones model fluid.