This application is intended to acquire an updated automatic four circle X-ray diffractometer for the measurement of single-crystals. This equipment must be structured with the usual components (generator, goniometer and detector), as well as with an accessory that enables measurements at low/high temperature._x000D_ The purpose of the request is threefold. It is intended to update the available scientific infrastructure in the field of diffraction, so that it allows the realization of measures of greater precision, with smaller crystals, of complex or low intensity phenomena (diffuse dispersion, modulated structures, etc.). Secondly, it is intended to release more measuring time that allows the realization of measures of longer requirements (electronic densities), given the current saturation of the available equipment. Finally, the application seeks to protect the diffraction service, which is basic to the research of many of the competitive groups that endorse the proposal, given the risks of breakdown of the old equipment available._x000D_ Also to be highlighted is the joint nature of the request, which proposes the purchase of this equipment to provide simultaneous and coordinated services to the two existing diffraction services in the Aragonese scientific framework (University of Zaragoza - CSIC), both to CEQMA (CSIC) -UZ), as to that of the SAI (UZ). This application has been endorsed by 10 competitive research groups that make an intensive use of this methodology.