Through the use of a synthetic high-throughput approach, 1,4-phenylenebis(methylidyne)-tetrakis(phosphonic acid), H8L, was investigated as a molecular building block for the formation of coordination frameworks with lanthanides (Ln = La, Nd, Gd, Dy) under hydrothermal conditions. Thereby, 14 new lanthanide phosphonates were discovered, categorized into three structure types, and their crystallization fields described. Structure type I comprises six compounds with the general formula Ln(H5L). The examples of Ln[(PO3H)(2)CH-C6H4-CH(PO3H)(PO3H2)]center dot 4H(2)O, where Ln = La, and Nd, reveal. two-dimensional coordination networks having a layered structure but differ in the layer stacking. Structure type II comprises four compounds of the general formula Ln(2)(H2L) and is represented by La-2[(HO3P)(O3P)CH-C6H4-CH(PO3)(PO3H)] center dot 8H(2)O, a layered structure with dimeric lanthanum coordination polyhedra. Four compounds of the type NaLn(H4L) are in stucture type III, which was solved from LaNa[(PO3H)(2)CH-C6H4-CH(PO3H)(2)]center dot 4H(2)O. This structure consists of a three-dimensional open framework with La3+ coordinated by bisphosphonate units in an exclusively bidentate fashion. It has a one-dimensional rhombic channel system that is occupied by sodium ions and water molecules acting as guests.