This description of the data structure and the sources implemented in SILICE prototype attempts to evidence the real possibility of creating custom citations indexes that fit with the research evaluation requirements, supplying specific data about the production and impact of the scientific literature in particular places or organizations. This proposal makes evident the need of creating services that do not depend on external criteria or metrics that could distort the performance or the appreciation of intrinsic scientific traditions. The main originality of this proposal is that it is entirely based on open sources that can be freely used with/without attribution, which allows to customize any element in the system and to critically select the most suitable sources according to the requirements and needs of the system. Another important innovation is that the citation repository is independent from the publication dataset, which permits to compute the global impact of publications, authors and organizations, without losing the global context of the Spanish scientific literature.