In a multiscale simulation approach, DFT was used to parameterize iron-nitrogen potentials in the [Fe(PM-BiA) 2 (NCS) 2 ] (PM-BiA = N-(2-pyridylmethylene)aminobiphenyl) SCO complex, which were subsequently used in MD simulations. This model allowed to probe the delicate interplay between crystalline and single-molecule effects and the influence of these factors on SCO. Finally, a (P ,T ) diagram for the complex was deduced. Calculating such diagrams is of tremendous help when comparing simulations with experiments, as evidenced by a study presenting an Ising Hamiltonian for a onedimensional SCO coordination polymer. Plane-wave DFT using the Hubbard model was applied in a study on the SCO in [Co(II)dpzca) 2 ],