Problems in experimental charge density modelling of rare earth atom complexes: the case of gadolinium Original Research Article

Difficulties to model the charge density of a gadolinium atom coordinated to organic ligands are discussed. Refinements using the available scattering factors did not lead to satisfactory results. This can be due to the inaccuracy of the wave functions calculation or to inherent difficulties in the treatment of f electrons whose specific nature would justify the use of a more realistic starting electron density model before performing the electron density calculations.