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Ab initio simulations of a multi-component alloy using density functional theory (DFT) were combined with experiments on thin films of the same material using X-ray photoelectron spectroscopy (XPS) to study the connection between the electronic and atomic structures of multi-component alloys. The DFT simulations were performed on an equimolar HfNbTiVZr multi-component alloy. Structure and charge transfer were evaluated using relaxed, non-relaxed, as well as elemental reference structures. The use of a fixed sphere size model allowed quantification of charge transfer, and separation into different contributions. The charge transfer was generally found to follow electronegativity trends and results in a reduced size mismatch between the elements, and thus causes a considerable reduction of the lattice distortions compared to a traditional assumption based on tabulated atomic radii. A calculation of the average deviation from the average radius (i.e. the so-called delta-parameter) based on the atomic Voronoi volumes gave a reduction of delta from ca. 6% (using the volumes in elemental reference phases) to ca. 2% (using the volumes in the relaxed multi-component alloy phase). The reliability of the theoretical results was confirmed by XPS measurements of a Hf22Nb19Ti18V19Zr21 thin film deposited by sputter deposition. The experimentally observed core level binding energy shifts (CLS), as well as peak broadening due to a range of chemical surroundings, for each element showed good agreement with the calculated DFT values. The single solid solution phase of the sample was confirmed by X-ray diffraction (XRD) and transmission electron microscopy (TEM) including energy dispersive spectroscopy (EDS) with nm-resolution. These observations show that the HfNbTiVZr solid solution phase is non-ideal, and that chemical bonding plays an important part in the structure formation, and presumably also in the properties. Our conclusions should be transferable to other multi-component a, Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2018-04834, 2019-05403, 2018-05973, 2019-05487]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University; Faculty Grant SFO at LiU [2009 00971]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program [FFL 15-0290]; RFBRRussian Foundation for Basic Research (RFBR) [20-02-00178]; Swedish e-Science Research Centre (SeRC)

High-pressure chemistry is known to inspire the creation of unexpected new classes of compounds with exceptional properties. Here, we employ the laser-heated diamond anvil cell technique for synthesis of a Dirac material BeN4. A triclinic phase of beryllium tetranitride tr-BeN4 was synthesized from elements at similar to 85 GPa. Upon decompression to ambient conditions, it transforms into a compound with atomic-thick BeN4 layers interconnected via weak van der Waals bonds and consisting of polyacetylene-like nitrogen chains with conjugated pi systems and Be atoms in square-planar coordination. Theoretical calculations for a single BeN4 layer show that its electronic lattice is described by a slightly distorted honeycomb structure reminiscent of the graphene lattice and the presence of Dirac points in the electronic band structure at the Fermi level. The BeN4 layer, i.e., beryllonitrene, represents a qualitatively new class of 2D materials that can be built of a metal atom and polymeric nitrogen chains and host anisotropic Dirac fermions., Funding Agencies|Army Research Office; Deutsche Forschungsgemeinschaft (DFG)German Research Foundation (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1]; Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [05K19WC1]; Alexander von Humboldt FoundationAlexander von Humboldt Foundation; Russian Science FoundationRussian Science Foundation (RSF) [18-12-00492]; Ministry of Science and Higher Education of the Russian Federation of Increase Competitiveness Program of NUST MISIS [K2-2020-026, 211]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; SeRCAgency for Science Technology & Research (ASTAR); Swedish Research Council (VR)Swedish Research Council [2019-05600]; Vinnova VINN Excellence Center Functional Nanoscale Materials (FunMat-2) [2016-05156]; Swedish Research CouncilSwedish Research CouncilEuropean Commission [2016-07213]; JTC-FLAGERA Project GRANSPORT; National Science Foundation-Earth SciencesNational Science Foundation (NSF) [EAR-1634415]; Department of Energy-GeosciencesUnited States Department of Energy (DOE) [DE-FG0294ER14466]; DOENNSAs Office of Experimental Sciences; DOE Office of ScienceUnited States Department of Energy (DOE) [DE-AC02-06CH11357]; [W911NF-19-2-0172]

There has been an increased interest to design “smart materials” which can self-assemble into complex structures in accordance to external factors such as for example electromagnetic fields. By designing particles with directional interactions one is able to control how particles will interact with each other. By means of both Monte Carlo and Molecular Dynamics simulations we study the interactions of three distinct types of models namely the self-assembly of off-centered dipoles, the charged patchy particle model in multivalent electrolytes, and an all atom model of [3,3Õ-cobalt(III) bis(1.2-dicarbollide)] and its interaction with solvent. Besides this there is also a short discussion about the long-range anisotropic interactions and ways by which one can calculate them.