Covariance Matrix of 111 plane of FCC, NVE solid -- Ordered

For a 32x32 parallelogram shaped region (1024 atoms) of a 111 FCC plane, I constructed the covariance matrix sampling 4000 snapshots separated by 10tau (the decorrelation time).

MATLAB eig() was used to diagonalize this 2048x2048 matrix for the eigenvectors and the eigenvalues. It took less than 5 mins.

Fig 1: is a histogram of 1/sqrt(covariance eigenvalues) for the ordered system.