On the power spectrum of undulations of simulated bilayers
  The best finite Fourier Series for a smooth surface $h(x,y)$ closest to the positions of heads of amphiphiles in the least-square sense, agrees fully with the Fourier coefficients obtained by a direct summation over raw data points. Both metods produce structure factors $S(q)$ containing all necessary features: small-q divergence, a minimum, the raise to the ubiquitous nearest neighbor peak near $q=2\pi/$(coll.diameter) and further peaks. The Laurent series is also discussed. 
J. Stecki
cond-mat.soft cond-mat.stat-mech