Decasils are a new order-disorder family of porous structures. All ordered and disordered decasil structures are built from one-dimensional chain-like basic building units that can be connected in different ways. Three simplest ordered framework structures of this family are possible: decasil types A, B, and C. Al decasil types possess cage-like voids that share 8MR pore openings to give a one-dimensional channel system. Using two different templates an ordered and a disordered form of the decasil family of structures have been synthesized. RUB-3 (decasil type A) was obtained with exo-2-aminobicyclo[2.2.1.]heptan as template and is ordered; RUB-4 was obtained with 3-azabicyclo[3.2.2]nonane as template and is disordered. The structure of RUB-3, which crystallizes in space group C 2/m (a = 14.039(2) , b = 13.602(2) , c = 7.428(1) , and β = 102.22(3)°), has been solved by model building and simulation of X-ray powder pattern and has been confirmed in a Rietveld analysis.