The calculations are performed with the revPBE functional 32, 33, a ‘Small’ frozen core and the double- ζ polarized (DZP) basis set.
ZEOLITE CRYSTALVIEWER CODE
Each structure’s coordinates and cell parameters are energy-minimized with the periodic density functional code BAND 30, as implemented in the Amsterdam Modeling Suite 31 (AMS). After selection of all systems with less than 301 atoms, each is manually filtered by removing redundant atom positions in case of fractional occupancies and adding missing hydrogen atoms where needed. Initial zeolite structures are collected from the public Database of Zeolite Structures 28 in the Crystallographic Information File (CIF) format, before conversion to the XYZ format with the Atomic Simulation Environment 29 (ASE) package. We envision future extensions of the data set to focus on derived geometries, covering structural defects and host-guest interactions. Our descriptor provides the complete optimization trajectories for each system with atomic positions, lattice vectors, atomic gradients and stress tensors at each step. In this first installment, we include properties for 204 out of the currently available 256 zeolite framework types in the database (a total of 226 unique geometries when also considering derived materials). Today, its contents are available online at the Database of Zeolite Structures 28, which we use as a source of initial structures for our data set. The atlas lists each unique framework type by its three-letter-code, as assigned by the by the Structure Commission of the International Zeolite Association (IZA). The documentation of fundamental zeolite framework types and derived materials has led to the publication of the well-known Atlas of Zeolite Structures 27 in several editions. To this day, a myriad of different zeolite framework types is available experimentally, and many more hypothetical structures can be derived 24, 25, 26. Because of their topology and synthetic flexibility, zeolites have various applications as adsorbents 18, 19, 20 and catalysts 17, 21, 22, 23. Their properties can be fine-tuned through synthesis of materials with specific pore size, or the inclusion of additional metal cation sites 14, 15, 16, 17. Zeolites are porous materials comprised of interconnected SiO 4 or AlO 4 tetrahedra. Motivated by this fact, we present a quantum-chemical data set for zeolites.
ZEOLITE CRYSTALVIEWER ARCHIVE
Materials Cloud Archive 10, 11 or the NOMAD database 12, 13).
Although there are already a handful of large computational data sets covering small organic molecules 7, 8, 9, such data is still scarce for larger periodic systems ( cf. Depending on the application, reference data are either experimental, or come from computationally more expensive ab initio calculations.
In order for such models to perform well, their empirical parameters require fitting to high-quality reference data. More recently, the use of pre-trained models has become increasingly popular due to their comparably low complexity and high accuracy on modern hardware 1, 2, 3, 4, 5, 6. Atomistic models are an essential tool for the prediction of thermodynamic, mechanical or biochemical properties of a substance.
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