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The article is devoted to the analysis of the changes in economic and legal context for commercial application of intellectual property created under federal budgetary financing. Special attention is given to the role of the state and to comparison of key elements of mechanisms for commercial application of intellectual property that are currently under implementation in Russia and in the West. A number of practical suggestions are presented aimed at improving government stimuli to commercialization of intellectual property created at budgetary expense.

We report a detail theoretical study of the electronic structure and phase stability of transition metal oxides MnO, FeO, CoO, and NiO in their paramagnetic cubic B1 structure by employing dynamical mean-field theory of correlated electrons combined with ab initio band-structure methods. Our calculations reveal that under pressure these materials exhibit a Mott insulator-metal transition (IMT) which is accompanied by a simultaneous collapse of local magnetic moments and lattice volume, implying a complex interplay between chemical bonding and electronic correlations. Moreover, our results for the transition pressure show a monotonous decrease from similar to 145 to 40 GPa, upon moving from MnO to CoO. In contrast to that, in NiO, magnetic collapse is found to occur at a remarkably higher pressure of similar to 429 GPa. We provide a unified picture of such a behavior and suggest that it is primarily a localized to itinerant moment behavior transition at the IMT that gives rise to magnetic collapse in transition metal oxides. ; Funding Agencies|Deutsche Forschungsgemeinschaft through Transregio [TRR 80]; Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST "MISIS" [K3-2016-027]; European Research Council [ERC-319286 QMAC]; Swiss National Science Foundation (NCCR MARVEL); Swedish Research Council (VR) [2015-04391]; Swedish Foundation for Strategic Research (SSF) [SRL 10-0026]; Knut and Alice Wallenberg Foundation [2014-2019]; Swedish Government Strategic Research Area Grant Swedish e-Science Research Centre (SeRC); Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]

We present a detailed theoretical study of the electronic, magnetic, and structural properties of magnesiowustite Fe-1 Mg-x(x) O with x in the range between 0 and 0.875 using a fully charge self-consistent implementation of the density functional theory plus dynamical mean-field theory method. In particular, we compute the electronic structure and phase stability of the rocksalt B1-structured (Fe,Mg) O at high pressures relevant for the Earths lower mantle. We find that upon compression paramagnetic (Fe,Mg) O exhibits a spin-state transition of Fe2+ ions from a high-spin to low-spin (HS-LS) state which is accompanied by a collapse of local magnetic moments. The HS-LS transition results in a substantial drop in the lattice volume by about 4%-8%, implying a complex interplay between electronic and lattice degrees of freedom. Our results reveal a strong sensitivity of the calculated transition pressure P-tr. upon addition of Mg. While, for Fe-rich magnesiowustite with Mg x amp;lt; 0.5, Ptr. is about 80 GPa, for Mg x = 0.75 it drops to 52 GPa, i. e., by 35%. This behavior is accompanied by a substantial change in the spin transition range from 50 to 140 GPa in FeO to 30 to 90 GPa for x = 0.75. In addition, the calculated bulk modulus (in the HS state) is found to increase by similar to 12% from 142 GPa in FeO to 159 GPa in (Fe,Mg) O with Mg x = 0.875. We find that the pressure-induced HS-LS transition has different consequences for the electronic properties of the Fe-rich and -poor (Fe,Mg) O. For the Fe-rich (Fe,Mg) O, the transition is found to be accompanied by a Mott insulator to a (semi) metal phase transition. In contrast to that, for x amp;gt; 0.25, (Fe,Mg) O remains insulating up to the highest studied pressures, implying a Mott-insulator to band-insulator phase transition at the HS-LS transformation. ; Funding Agencies|Deutsche Forschungsgemeinschaft [Transregio TRR 80]; Ministry of Education and Science of the Russian Federation [K3-2016-027]; Russian Foundation for Basic Researches [16-02-00797]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

We perform a comprehensive theoretical study of the pressure-induced evolution of the electronic structure, magnetic state, and phase stability of the late transition metal monoxides MnO, FeO, CoO, and NiO using a fully charge self-consistent DFT+dynamical mean-field theory method. Our results reveal that the pressure-induced Mott insulator-to-metal phase transition in MnO-NiO is accompanied by a simultaneous collapse of local magnetic moments and lattice volume, implying a complex interplay between chemical bonding and electronic correlations. We compute the pressure-induced evolution of relative weights of the different valence states and spin-state configurations. Employing the concept of fluctuating valence in a correlated solid, we demonstrate that in MnO, FeO, and CoO a Mott insulator-metal transition and collapse of the local moments is accompanied by a sharp crossover of the spin-state and valence configurations. Our microscopic explanation of the magnetic collapse differs from the accepted picture and points out a remarkable dynamical coexistence (frustration) of the high-, intermediate-, and low-spin states. In particular, in MnO, the magnetic collapse is found to be driven by the appearance of the intermediate-spin state (IS), competing with the low-spin (LS) state; in FeO, we observe a conventional high-spin to low-spin (HS-LS) crossover. Most interestingly, in CoO, we obtain a remarkable (dynamical) coexistence of the HS and LS states, i.e., a HS-LS frustration, up to high pressure. Our results demonstrate the importance of quantum fluctuations of the valence and spin states for the understanding of quantum criticality of the Mott transitions. © 2020 American Physical Society. ; We thank L. Pourovskii, A. Georges, R. Jeanloz, G. Kh. Rozenberg, and D. I. Khomskii for valuable discussions. Theoretical analysis of the magnetic and valence states as well as of the structural properties of MnO, FeO, CoO, and NiO was supported by the Russian Science Foundation (project No. 18-12-00492). Simulations of the electronic structure were supported by the state assignment of Minobrnauki of Russia (theme "Electron" No. AAAA-A18-118020190098-5). Support from Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant No. KAW-2018.0194), the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (Faculty Grant SFOMatLiU No. 2009 00971), and the Swedish e-Science Research Centre (SeRC) are gratefully acknowledged.

We perform a comprehensive theoretical study of the pressure-induced evolution of the electronic structure, magnetic state, and phase stability of the late transition metal monoxides MnO, FeO, CoO, and NiO using a fully charge self-consistent DFT-Pdynamical mean-field theory method. Our results reveal that the pressure-induced Mott insulator-to-metal phase transition in MnO-NiO is accompanied by a simultaneous collapse of local magnetic moments and lattice volume, implying a complex interplay between chemical bonding and electronic correlations. We compute the pressure-induced evolution of relative weights of the different valence states and spin-state configurations. Employing the concept of fluctuating valence in a correlated solid, we demonstrate that in MnO, FeO, and CoO a Mott insulator-metal transition and collapse of the local moments is accompanied by a sharp crossover of the spin-state and valence configurations. Our microscopic explanation of the magnetic collapse differs from the accepted picture and points out a remarkable dynamical coexistence (frustration) of the high-, intermediate-, and low-spin states. In particular, in MnO, the magnetic collapse is found to be driven by the appearance of the intermediate-spin state (IS), competing with the low-spin (LS) state; in FeO, we observe a conventional high-spin to low-spin (HS-LS) crossover. Most interestingly, in CoO, we obtain a remarkable (dynamical) coexistence of the HS and LS states, i.e., a HS-LS frustration, up to high pressure. Our results demonstrate the importance of quantum fluctuations of the valence and spin states for the understanding of quantum criticality of the Mott transitions. ; Funding Agencies|Russian Science FoundationRussian Science Foundation (RSF) [18-12-00492]; Minobrnauki of Russia [AAAA-A18-118020190098-5]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW-2018.0194]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]; Swedish e-Science Research Centre (SeRC)

We discuss the electronic, magnetic, and related structural transitions in the iron-based Mott insulators under high pressures relevant to the Earths lower mantle conditions. The paper focuses on the above-mentioned topics based primarily on our theoretical analysis and various experimental studies employing synchrotron X-ray diffraction, Fe-57 Mossbauer spectroscopy, and electrical transport measurements. We review the main theoretical tools employed for the analysis of the properties of materials with strongly interacting electrons and discuss the problems of theoretical description of such systems. In particular, we discuss a state-of-the-art method for calculating the electronic structure of strongly correlated materials, the DFT + DMFT method, which merges standard band-structure techniques (DFT) with dynamical mean-field theory of correlated electrons (DMFT). We employ this method to study the pressure-induced magnetic collapse in Mott insulators, such as wustite (FeO), magnesiowustite (Fe1-xMgx)O (x=0.25 and 0.75) and goethite (FeOOH), and explore the consequences of the magnetic collapse for the electronic structure and phase stability of these materials. We show that the paramagnetic cubic B1-structured FeO and (Fe,Mg)O and distorted orthorhombic (Pnma) FeOOH exhibit upon compression a high-to low-spin (HS-LS) transition, which is accompanied by a simultaneous collapse of local moments. However, the HS-LS transition is found to have different consequences for the electronic properties of these compounds. For FeO and (Fe0.75Mg0.25)O, the transition is found to be accompanied by a Mott insulator-to-metal phase transition. In contrast to that, both (Fe0.25Mg0.75)O and FeOOH remain insulating up to the highest studied pressures, indicating that a Mott insulator to band insulator phase transition takes place. Our combined theoretical and experimental studies indicate a crossover between localized to itinerant moment behavior to accompany magnetic collapse of Fe ions. ; Funding Agencies|Deutsche Forschungsgemeinschaft through Transregio TRR [80]; Ministry of Education and Science of the Russian Federation [K3-2016-027, 14.Y26.31.0005]; Russian Foundation for Basic Research [16-02-01027]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Israel Science Foundation [1189/14]

We perform a theoretical study of the electronic structure and magnetic properties of the prototypical magnetic MAX-phase Mn2GaC with the main focus given to the origin of magnetic interactions in this system. Using the density functional theory+dynamical mean-field theory (DFT+DMFT) method, we explore the effects of electron-electron interactions and magnetic correlations on the electronic properties, magnetic state, and spectral weight coherence of paramagnetic and magnetically ordered phases of Mn2GaC. We also benchmark the DFT-based disordered local moment approach for this system by comparing the obtained electronic and magnetic properties with that of the DFT+DMFT method. Our results reveal a complex magnetic behavior characterized by a near degeneracy of the ferro- and antiferromagnetic configurations of Mn2GaC, implying a high sensitivity of its magnetic state to fine details of the crystal structure and unit-cell volume, consistent with experimental observations. We observe robust local-moment behavior and orbital-selective incoherence of the spectral properties of Mn2GaC, implying the importance of orbital-dependent localization of the Mn 3d states. We find that Mn2GaC can be described in terms of local magnetic moments, which may be modeled by DFT with disordered local moments. However, the magnetic properties are dictated by the proximity to the regime of formation of local magnetic moments, in which the localization is in fact driven by Hund's exchange interaction, and not the Coulomb interaction. © 2022 authors. Published by the American Physical Society. ; Support from the Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant No. KAW-2018.0194), the Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linköping University (Faculty Grant SFO-Mat-LiU No. 2009 00971), the Swedish e-Science Research Centre (SeRC), the Swedish Research Council (VR) Grant No. 2019-05600, and Swedish Foundation for Strategic Research (SSF) Project No. EM16-0004 is ...

We perform a theoretical study of the electronic structure and magnetic properties of the prototypical magnetic MAX-phase Mn2GaC with the main focus given to the origin of magnetic interactions in this system. Using the density functional theory+dynamical mean-field theory (DFT+DMFT) method, we explore the effects of electron-electron interactions and magnetic correlations on the electronic properties, magnetic state, and spectral weight coherence of paramagnetic and magnetically ordered phases of Mn2GaC. We also benchmark the DFT-based disordered local moment approach for this system by comparing the obtained electronic and magnetic properties with that of the DFT+DMFT method. Our results reveal a complex magnetic behavior characterized by a near degeneracy of the ferro-and antiferromagnetic configurations of Mn2GaC, implying a high sensitivity of its magnetic state to fine details of the crystal structure and unit-cell volume, consistent with experimental observations. We observe robust local-moment behavior and orbital-selective incoherence of the spectral properties of Mn2GaC, implying the importance of orbital-dependent localization of the Mn 3d states. We find that Mn2GaC can be described in terms of local magnetic moments, which may be modeled by DFT with disordered local moments. However, the magnetic properties are dictated by the proximity to the regime of formation of local magnetic moments, in which the localization is in fact driven by Hunds exchange interaction, and not the Coulomb interaction. ; Funding Agencies|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 [2009 00971]; Swedish e-Science Research Centre (SeRC); Swedish Research Council (VR)Swedish Research Council [2019-05600]; Swedish Foundation for Strategic Research (SSF)Swedish Foundation for Strategic Research [EM16-0004]; Russian Science FoundationRussian Science Foundation (RSF) [18-12-00492]; state assignment of Minobrnauki of Russia [AAAA-A18-1180201900985]; Swedish Research CouncilSwedish Research CouncilEuropean Commission [2016-07213]

We compute the phonon dispersion, density of states, and the Grüneisen parameters of bulk palladium in the combined density functional theory (DFT) and dynamical mean-field theory. We find good agreement with experimental results for ground-state properties (equilibrium lattice parameter and bulk modulus) and the experimentally measured phonon spectra. We demonstrate that at temperatures Tâ‰20K the phonon frequency in the vicinity of the Kohn anomaly, ωT1(qK), strongly decreases. This is in contrast to DFT where this frequency remains essentially constant in the whole temperature range. Apparently, correlation effects reduce the restoring force of the ionic displacements at low temperatures, leading to a mode softening. © 2020 American Physical Society. ; We are grateful to Ferdi Aryasetiawan, Milos Radonjić, and Weiwei Sun for stimulating discussions. W.H.A. thanks Levente Vitos for the kind hospitality at KTH Stockholm. I.D.M. acknowledges support by the appointment to the JRG program at the APCTP through the Science and Technology Promotion Fund and Lottery Fund of the Korean Government, as well as support by the Korean Local Governments, Gyeongsangbuk-do Province, and Pohang City. Part of the computations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC) at Beskow. Financial support offered by the Augsburg Center for Innovative Technologies, and by the Deutsche Forschungsgemeinschaft (through TRR 80/F6) is gratefully acknowledged. I.L. acknowledges support by the state assignment of Minobrnauki of Russia (theme "Electron" No. AAAA-A18-118020190098-5).

Extreme pressures and temperatures are known to drastically affect the chemistry of iron oxides, resulting in numerous compounds forming homologous series nFeOmFe2O3 and the appearance of FeO2. Here, based on the results of in situ single-crystal x-ray diffraction, Mössbauer spectroscopy, x-ray absorption spectroscopy, and density-functional theory+dynamical mean-field theory calculations, we demonstrate that iron in high-pressure cubic FeO2 and isostructural FeO2H0.5 is ferric (Fe3+), and oxygen has a formal valence less than 2. Reduction of oxygen valence from 2, common for oxides, down to 1.5 can be explained by a formation of a localized hole at oxygen sites. © 2021 American Physical Society. ; We acknowledge the Deutsches Elektronen-Synchrotron (DESY, PETRA III), the European Synchrotron Radiation Facility (ESRF), and the Advance Photon Source (APS) for provision of beamtime. N. D. and L. D. thank the Federal Ministry of Education and Research, Germany (BMBF, Grant No. 05K19WC1) and the Deutsche Forschungsgemeinschaft (DFG Projects No. DU 954–11/1, No. DU 393–9/2, and No. DU 393–13/1) for financial support. N. D. and I. A. A. thank the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (Faculty Grant SFO-Mat-LiU No. 2009 00971). Electronic structure calculations were supported by the Russian Science Foundation (Project No. 18-12-00492). Theoretical analysis of chemical bonding was supported by the Ministry of Science and Higher Education of the Russian Federation in the framework of Increase Competitiveness Program of NUST "MISIS" (No. K2-2019-001) implemented by a governmental decree, No. 211. Support from the Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant No. KAW-2018.0194), the Swedish Government Strategic Research Areas and SeRC, and the Swedish Research Council (VR) Grant No. 2019-05600 is gratefully acknowledged.