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The crystal structure of the mineral decrespignyite-(Y) from the Paratoo copper mine (South Australia) has been obtained by applying δ recycling direct methods to 3D electron diffraction (ED) data followed by Rietveld refinements of synchrotron data. The unit cell is a= 8.5462(2), c= 22.731(2) Å and V= 1437.8(2) Å3, and the chemical formula for Z=1 is (Y10.35REE1.43Ca0.52Cu5.31)Σ17.61(CO3)14Cl2.21(OH)16.79⋅18.35H2O (REE: rare earth elements). The ED data are compatible with the trigonal P3¯m1 space group (no. 164) used for the structure solution (due to the disorder affecting part of the structure, the possibility of a monoclinic unit cell cannot completely be ruled out). The structure shows metal layers perpendicular to [001], with six independent positions for Y, REE and Cu (sites M1 to M4 are full, and sites M5 and M6 are partially vacant), and two other sites, Cu1 and Cu2, partially occupied by Cu. One characteristic of decrespignyite is the existence of hexanuclear (octahedral) oxo-hydroxo yttrium clusters [Y6(μ6-O)(μ3-OH)8O24] (site M1) with the 24 bridging O atoms belonging to two sets of symmetry-independent (CO3)2− ions, with the first set (2×) along a ternary axis giving rise to a layer of hexanuclear clusters and the second set (6×) tilted and connecting the hexanuclear clusters with hetero-tetranuclear ones hosting Cu, Y and REE (M2 and M3 sites). The rest of the crystal structure consists of two consecutive M3 + M4 layers containing the partially occupied M5, M6, and Cu2 sites and additional carbonate anions in between. The resulting structure model is compatible with the chemical analysis of the type material which is poorer in Cu and richer in (REE, Y) than the above-described material. ; This research received financial support from the Spanish MINECO (project RTI2018-098537-B-C21), from FEDER and from the European Union Fund for Regional Development POCTEFA (grant no. EFA 194/16 TNSI). We acknowledge support for the publication fee from the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). ; Peer reviewed

In this work a new ultrafast data collection strategy for electron diffraction tomography is presented that allows reducing data acquisition time by one order of magnitude. This methodology minimizes the radiation damage of beam-sensitive materials, such as microporous materials. This method, combined with the precession of the electron beam, provides high quality data enabling the determination of very complex structures. Most importantly, the implementation of this new electron diffraction methodology is easily affordable in any modern electron microscope. As a proof of concept, we have solved a new highly complex zeolitic structure named ITQ-58, with a very low symmetry (triclinic) and a large unit cell volume (1874.6 Å), containing 16 silicon and 32 oxygen atoms in its asymmetric unit, which would be very difficult to solve with the state of the art techniques. ; The authors gratefully acknowledge financial support of European Research Council (ERC-2014-AdG ref 671093 "MATching zeolite SYNthesis with CATalytic activity"), Spanish Government (MAT2015-71842-P (MINECO/FEDER), MAT2012-38567-C02-01 and Severo Ochoa SEV-2012-0267), and Generalitat Valenciana (Project Prometeo). E.M. was also supported by the Italian project FIR2013 Exploring the Nanoworld. ; Peer Reviewed

[EN] In this work a new ultrafast data collection strategy for electron diffraction tomography is presented that allows reducing data acquisition tithe by one order of Magnitude.,,This Methodology minimizes the radiation damage of, beam-sensitive materials, such as microporous materials. This method, combined with the precession of the electron beam, provides high quality data enabling the determination of very complex structures. Most importantly,, the implementation of this new, electron diffraction methodology is, easily affordable in any modem electron Microscope. As a proof of concept, we have solved a new highly complex zeolitic structure named ITQ-58, with a very low symmetry (triclinic) and a large unit cell volume (1874.61(3)), containing 16 silicon and 32 oxygen atoms in its asymmetric unit, which would be very difficult to solve with the state of the art techniques. ; The authors gratefully acknowledge financial support of European Research Council (ERC-2014-AdG ref 671093 "MATching zeolite SYNthesis with CATalytic activity"), Spanish Government (MAT2015-71842-P (MINECO/FEDER), MAT2012-38567-C02-01 and Severo Ochoa SEV-2012-0267), and Generalitat Valenciana (Project Prometeo). E.M. was also supported by the Italian project FIR2013 Exploring the Nanoworld. Authors thank beamline MSPD at Spanish Synchrotron ALBA for beam time allocation. We acknowledge JEOL Japan, JEOL Europe, and specially Junichi Morimoto from JEOL Europe for the assistance during the specific alignments of the microscope. Finally, authors specially thank the Electron Microscopy Service of the Universitat Politecnica de Valencia and, in particular, Manuel J. Planes and Jose L. Moya for their invaluable support for setting up the EDT data acquisition. Original data (collected EDT frames and integrated intensities) can be requested directly from corresponding authors. ; Simancas-Coloma, J.; Simancas Coloma, R.; Bereciartua-Pérez, PJ.; Jorda Moret, JL.; Rey Garcia, F.; Corma Canós, A.; Nicolopoulos ., S. (2016). Ultrafast Electron ...