SCELib: a parallel computational library of molecular properties in the single centre approach. Nature of problem: In this set of codes an efficient procedure is implemented to describe the wavefunction and related molecular properties of a polyatomic molecular system within the Single Centre of Expansion (SCE) framework of reference. The resulting SCE wavefunction, electron density, electrostatic and exchange/correlation potentials can then be used via a proper Application Program Interface (AFI) to describe the target molecular system in electron-molecule scattering calculations. The generated molecular properties which are expanded over a single centre turn out to be of more general application and some possible uses in quantum chemistry, biomodelling and drug design are also outlined. (Source: