For the correct experimental determination of the charge-density distribution within crystalline structures, reliable high-resolution diffraction data are imperative. The refinement of the true, experimental charge-density requires the application of sophisticated models, like the Hansen & Coppens Multipole Model (Acta Cryst. (1978) A34, 909–921) or Coppens & Volcov X-ray constrained wave functions (Acta Cryst. (2004) A60, 111-119). Only such models allow for the deconvolution of the vibrational smearing from the anisotropic atomic density or the system wave function and subsequently revealing insight to the chemical properties.
The collection of such high-resolution data impose strict demands on the experimental setup. While perfect crystal quality is sometimes not achievable, the development of advanced hardware and software clears the path for novel charge-density determinations.
The Rigaku XtaLab Synergy series provides the fusion of high-end hard- and software, providing new possibilities for experimental charge- density determination.