1 This document is the Accepted Manuscript version of a Published Work that appeared in final form in Crystal Growth & Design, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/pdf/10.1021/acs.cgd.6b01732 A Metal-Organic Framework Based on a Tetra- Arylextended Calix[4]pyrrole Ligand: Structure Control through the Covalent Connectivity in the Linker. Jordi Aguilera-Sigalat, a Cristina Sáenz de Pipaón, a Daniel Hernández-Alonso, a Eduardo C. Escudero-Adán, a José Ramón Galan-Mascarós,* ,a,b Pablo Ballester* ,a,b a Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avgda. Països Catalans 16, 43007 Tarragona, Spain. b ICREA, Passeig Lluís Companys, 23, 03018 Barcelona, Spain ABSTRACT. The preparation of isomeric metal-organic frameworks in which the network topology is controlled by the different covalent connectivity of the organic ligand is an important step forward in the design of new functional materials. In this context, macrocyclic organic ligands able to accommodate suitable guests in their own polar internal cavities are appealing candidates to act as multidentate linkers, which could potentially self-assemble into hierarchical porous