From Spinach Documentation Wiki
Molecular connectivity matrix calculator with N*log(N) asymptotic complexity scaling with respect to the number or atoms.
xyz - an array with N rows and three columns, giving the Cartesian coordinates of each particle
r0 - the distance below which the particles are to be considered "connected"
conmatrix - a sparse logical matrix containing 1 at the positions corresponding to the connected particles
Version 2.1, authors: Ilya Kuprov