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Key challenge in transitional countries is effective decentralized local governance with strong capacities for dealing with new rural development programming instruments. In this paper we have examined the attitudes of local rural development actors (RDA) in Serbia on rural development policy priorities, in particular their attitudes on beneficiaries of rural development measures, policy objectives, and the most efficient strategies of rural development. We also analysed whether the respondents' attitudes differ depending on the socio-economic characteristic of surveyed regions (South and North of Serbia). Data on attitudes of RDAs were collected through direct survey with representatives of 30 rural communities, and analysed using descriptive statistics methods and Ajzen's theory of planned behaviour. Results indicate that respondents' attitudes on rural policy are conservative and oriented towards objectives related to agriculture and interests of farmers and that socio-economic characteristic of the regions contribute to distinction in attitudes of RDAs.

The goal of this paper is to present a method to establish the typology of rural areas in Serbia. Initially the OECD rurality criterion was applied to define the rural areas in Serbia. Subsequently, relevant indicators were selected (demographic, geographic, economic, employment-related, human capital, agricultural, tourism and infrastructure) and used to define and distinguish relatively homogeneous rural regions, based on correlation analysis, factor analysis (VARIMAX method) and cluster analysis. Cluster analysis revealed six regions of different sizes and characteristics. Practical considerations reduced this to four types, resulting in a robust scheme which accurately reflects the heterogeneous nature of rural Serbia.

A generalized extraction procedure for magnetic interactions using effective Hamiltonians is presented that is applicable to systems with more than two sites featuring local spins S i ≥ 1. To this end, closed, nonrecursive expressions pertaining to chains of arbitrary equal spins are derived with the graphical method of angular momentum. The method is illustrated by extracting magnetic couplings from ab initio calculations on a [CaMn 3 (IV) O 4 ] cubane. An extension to nonsequential coupling schemes proves conducive to expressing additional symmetries of certain spin Hamiltonians.

The 5d^{1} ordered double perovskites present an exotic playground for studying novel multipolar physics due to large spin-orbit coupling. We present Re L_{3} edge resonant inelastic x-ray scattering (RIXS) results that reveal the presence of the dynamic Jahn-Teller effect in the A_{2}MgReO_{6} (A=Ca, Sr, Ba) family of 5d^{1} double perovskites. The spin-orbit excitations in these materials show a strongly asymmetric line shape and exhibit substantial temperature dependence, indicating that they are dressed with lattice vibrations. Our experimental results are explained quantitatively through a RIXS calculation based on a spin-orbit-lattice entangled electronic ground state with the dynamic Jahn-Teller effect taken into consideration. We find that the spin-orbit-lattice entangled state is robust against magnetic and structural phase transitions as well as against significant static Jahn-Teller distortions. Our results illustrate the importance of including vibronic coupling for a complete description of the ground state physics of 5d^{1} double perovskites.

In this work, we demonstrate how to efficiently compute the one- and two-body reduced density matrices within the spin-adapted full configuration interaction quantum Monte Carlo (FCIQMC) method, which is based on the graphical unitary group approach (GUGA). This allows us to use GUGA-FCIQMC as a spin-pure configuration interaction (CI) eigensolver within the complete active space self-consistent field (CASSCF) procedure and hence to stochastically treat active spaces far larger than conventional CI solvers while variationally relaxing orbitals for specific spin-pure states. We apply the method to investigate the spin ladder in iron-sulfur dimer and tetramer model systems. We demonstrate the importance of the orbital relaxation by comparing the Heisenberg model magnetic coupling parameters from the CASSCF procedure to those from a CI-only (CASCI) procedure based on restricted open-shell Hartree-Fock orbitals. We show that the orbital relaxation differentially stabilizes the lower-spin states, thus enlarging the coupling parameters with respect to the values predicted by ignoring orbital relaxation effects. Moreover, we find that, while CASCI results are well fit by a simple bilinear Heisenberg Hamiltonian, the CASSCF eigenvalues exhibit deviations that necessitate the inclusion of biquadratic terms in the model Hamiltonian.

Polynuclear transition-metal (PNTM) clusters owe their catalytic activity to numerous energetically low-lying spin states and stable oxidation states. The characterization of their electronic structure represents one of the greatest challenges of modern chemistry. We propose a theoretical framework that enables the resolution of targeted electronic states with ease and apply it to two [Fe(III) 4 S 4 ] cubanes. Through direct access to their many-body wave functions, we identify important correlation mechanisms and their interplay with the geometrical distortions observed in these clusters, which are core properties in understanding their catalytic activity. The simulated magnetic coupling constants predicted by our strategy allow us to make qualitative connections between spin interactions and geometrical distortions, demonstrating its predictive power. Moreover, despite its simplicity, the strategy provides magnetic coupling constants in good agreement with the available experimental ones. The complexes are intrinsically frustrated anti-ferromagnets, and the obtained spin structures together with the geometrical distortions represent two possible ways to release spin frustration (spin-driven Jahn-Teller distortion). Our paradigm provides a simple, yet rigorous, route to uncover the electronic structure of PNTM clusters and may be applied to a wide variety of such clusters.

Accurate ab initio calculations of 3d transition metal monoxide molecules have attracted extensive attention because of their relevance in physical and chemical science as well as theoretical challenges in treating strong electron correlation. Meanwhile, recent years have witnessed the rapid development of the full configuration interaction quantum Monte Carlo (FCIQMC) method to tackle electron correlation. In this study, we carry out FCIQMC simulations to ScO, TiO, and VO molecules and obtain accurate descriptions of 13 low-lying electronic states (ScO 2 Σ + , 2 Δ, 2 Π; TiO 3 Δ, 1 Δ, 1 Σ + , 3 Π, 3 Φ; VO 4 Σ - , 4 Φ, 4 Π, 2 Γ, 2 Δ), including states that have significant multi-configurational character. The FCIQMC results are used to assess the performance of several other wave function theory and density functional theory methods. Our study highlights the challenging nature of the electronic structure of transition metal oxides and demonstrates FCIQMC as a promising technique going forward to treat more complex transition metal oxide molecules and materials.

Oxygen vacancies are ubiquitous in TiO 2 and play key roles in catalysis and magnetism applications. Despite being extensively investigated, the electronic structure of oxygen vacancies in TiO 2 remains controversial both experimentally and theoretically. Here, we report a study of a neutral oxygen vacancy in TiO 2 using state-of-the-art quantum chemical electronic structure methods. We find that the ground state is a color center singlet state in both the rutile and the anatase phases of TiO 2 . Specifically, embedded coupled cluster with singles, doubles, and perturbative triples calculations find, for an oxygen vacancy in rutile, that the lowest triplet state energy is 0.6 eV above the singlet state, and in anatase, the triplet state energy is higher by 1.4 eV. Our study provides fresh insights into the electronic structure of the oxygen vacancy in TiO 2 , clarifying earlier controversies and potentially inspiring future studies of defects with correlated wave function theories.

We present NECI, a state-of-the-art implementation of the Full Configuration Interaction Quantum Monte Carlo (FCIQMC) algorithm, a method based on a stochastic application of the Hamiltonian matrix on a sparse sampling of the wave function. The program utilizes a very powerful parallelization and scales efficiently to more than 24 000 central processing unit cores. In this paper, we describe the core functionalities of NECI and its recent developments. This includes the capabilities to calculate ground and excited state energies, properties via the one- and two-body reduced density matrices, as well as spectral and Green's functions for ab initio and model systems. A number of enhancements of the bare FCIQMC algorithm are available within NECI, allowing us to use a partially deterministic formulation of the algorithm, working in a spin-adapted basis or supporting transcorrelated Hamiltonians. NECI supports the FCIDUMP file format for integrals, supplying a convenient interface to numerous quantum chemistry programs, and it is licensed under GPL-3.0.

PySCF is a Python-based general-purpose electronic structure platform that supports first-principles simulations of molecules and solids as well as accelerates the development of new methodology and complex computational workflows. This paper explains the design and philosophy behind PySCF that enables it to meet these twin objectives. With several case studies, we show how users can easily implement their own methods using PySCF as a development environment. We then summarize the capabilities of PySCF for molecular and solid-state simulations. Finally, we describe the growing ecosystem of projects that use PySCF across the domains of quantum chemistry, materials science, machine learning, and quantum information science.

In this Article we describe the OpenMolcas environment and invite the computational chemistry community to collaborate. The open-source project already includes a large number of new developments realized during the transition from the commercial MOLCAS product to the open-source platform. The paper initially describes the technical details of the new software development platform. This is followed by brief presentations of many new methods, implementations, and features of the OpenMolcas program suite. These developments include novel wave function methods such as stochastic complete active space self-consistent field, density matrix renormalization group (DMRG) methods, and hybrid multiconfigurational wave function and density functional theory models. Some of these implementations include an array of additional options and functionalities. The paper proceeds and describes developments related to explorations of potential energy surfaces. Here we present methods for the optimization of conical intersections, the simulation of adiabatic and nonadiabatic molecular dynamics, and interfaces to tools for semiclassical and quantum mechanical nuclear dynamics. Furthermore, the Article describes features unique to simulations of spectroscopic and magnetic phenomena such as the exact semiclassical description of the interaction between light and matter, various X-ray processes, magnetic circular dichroism, and properties. Finally, the paper describes a number of built-in and add-on features to support the OpenMolcas platform with postcalculation analysis and visualization, a multiscale simulation option using frozen-density embedding theory, and new electronic and muonic basis sets.

In existing theoretical approaches to core-level excitations of transition-metal ions in solids relaxation and polarization effects due to the inner core hole are often ignored or described phenomenologically. Here we set up an ab initio computational scheme that explicitly accounts for such physics in the calculation of x-ray absorption and resonant inelastic x-ray scattering spectra. Good agreement is found with experimental transition-metal L-edge data for the strongly correlated d 9 cuprate Li 2 CuO 2 , for which we determine the absolute scattering intensities. The newly developed methodology opens the way for the investigation of even more complex d n electronic structures of group VI B to VIII B correlated oxide compounds.

The article contains the results of the ecological and hygienic diagnostics of conditions of lands of areas of different sizes and varying degrees of urbanization, located in different agro-climatic conditions of European Russia (the southern Astrakhan region, he city of Moscow). Assessments of the state of territories use a new approach to rationing of Hg according to quantitative ratios of the content of its thermoforms in soils, grounds and alluvium (in litho substrate). The method of diagnostics is based on known properties of Hg forms: their geochemical activity (migration mobility) and toxicity decline along with the increment of the Hg temperature threshold of the release in the process of continuous warming up of the litho substrate sample (up to 1100°C). Thermoforms are not tied to specific minerals or chemicals and are conditionally designated as FR (Free: <180°C), CL (Chloride: 180-250°C), FS and CS (physically and chemically sorbed: 250-400°C), SU (Sulfide: 400-500°C) IS (isomorphic: >500°C) Hg forms. Among forms, also conditionally according to complexes of low, medium and high temperature variations(FR + CL, FS + CS and SU + IZ, respectively, there are selected groups of «mobile», «sustainable» and «inert» forms. For technogenic Hg there is characterized the predominance in the sample of «mobile» and to lesser extent degree - «stable» thermoforms. The more intensive this predominance is, the higher is environmental hazard. The natural accumulation is diagnosed by the presence and prevalence of the sum of moderate - and high-temperature inert forms of Hg. According to the ratios of Hg content, its forms and groups, as well as the density of correlationships between them, 6 indices of the conditions of soils and alluvium were developed by ourselves.Main coefficients out of indices on informativeness of results of diagnostics are the following factors: Endogenous input, Geochemical activity and Hg mobility. With regard to the combination of variability in indices, the total amount of Hg, the genesis and intensity of its accumulation (natural or anthropogenic), there were also developed ranking scales of the ecological and hygienic condition of the land areas and surface water bodies. As a result, on the base of such approach to the regulation of Hg the information value of assessments of mercury contamination of land significantly increased. At the objects of assessments there were identified following areas: foci of the manifestation of Hg hypolimnetic emanations on the landscape surface - dispersion halos in the areas of the Earth crust fracture (the dome of the Astrakhan gas condensate field); environmentally dangerous (sometimes even at a low total content of Hg) parts of cities, towns, their districts, as well as beds of watercourses and water reservoirs bottom (the Volga river valley and delta, the Lefortovo quarter in Moscow). There was also diagnosed the threshold of the background distribution of gross Hg content detected = 0.2-0.3 mg/kg. Its magnitude is consistent with domestic and abroad safe levels of Hg accumulation in soils = 0.3-0.4 mg/kg. The approach provides the differentiation of the environmental hazard lands. Technology of the approach can be used in the development of normative Document for the diagnosis of environmental and sanitary condition of territories in the system of Classifications of hazard of waste, in decontamination of territories, water areas and land zoning according to the criteria of natural or anthropogenic Hg accumulation.

Large anisotropic exchange in 5d and 4d oxides and halides open the door to new types of magnetic ground states and excitations, inconceivable a decade ago. A prominent case is the Kitaev spin liquid, host of remarkable properties such as protection of quantum information and the emergence of Majorana fermions. Here we discuss the promise for spin-liquid behavior in the 4d 5 honeycomb halide α-RuCl 3 . From advanced electronic-structure calculations, we find that the Kitaev interaction is ferromagnetic, as in 5d 5 iridium honeycomb oxides, and indeed defines the largest superexchange energy scale. A ferromagnetic Kitaev coupling is also supported by a detailed analysis of the field-dependent magnetization. Using exact diagonalization and density-matrix renormalization group techniques for extended Kitaev-Heisenberg spin Hamiltonians, we find indications for a transition from zigzag order to a gapped spin liquid when applying magnetic field. Our results offer a unified picture on recent magnetic and spectroscopic measurements on this material and open new perspectives on the prospect of realizing quantum spin liquids in d 5 halides and oxides in general.

Much consideration has been given to the role of spin-orbit coupling (SOC) in 5d oxides, particularly on the formation of novel electronic states and manifested metal-insulator transitions (MITs). SOC plays a dominant role in 5d(5) iridates (Ir(4+)), undergoing MITs both concurrent (pyrochlores) and separated (perovskites) from the onset of magnetic order. However, the role of SOC for other 5d configurations is less clear. For example, 5d(3) (Os(5+)) systems are expected to have an orbital singlet with reduced effective SOC. The pyrochlore Cd2Os2O7 nonetheless exhibits a MIT entwined with magnetic order phenomenologically similar to pyrochlore iridates. Here, we resolve the magnetic structure in Cd2Os2O7 with neutron diffraction and then via resonant inelastic X-ray scattering determine the salient electronic and magnetic energy scales controlling the MIT. In particular, SOC plays a subtle role in creating the electronic ground state but drives the magnetic order and emergence of a multiple spin-flip magnetic excitation.

A promising route to tailoring the electronic properties of quantum materials and devices rests on the idea of orbital engineering in multilayered oxide heterostructures. Here we show that the interplay of interlayer charge imbalance and ligand distortions provides a knob for tuning the sequence of electronic levels even in intrinsically stacked oxides. We resolve in this regard the d-level structure of layered Sr2IrO4 by electron spin resonance. While canonical ligand-field theory predicts g||-factors less than 2 for positive tetragonal distortions as present in Sr2IrO4, the experiment indicates g|| is greater than 2. This implies that the iridium d levels are inverted with respect to their normal ordering. State-of-the-art electronic-structure calculations confirm the level switching in Sr2IrO4, whereas we find them in Ba2IrO4 to be instead normally ordered. Given the nonpolar character of the metal-oxygen layers, our findings highlight the tetravalent transition-metal 214 oxides as ideal platforms to explore d-orbital reconstruction in the context of oxide electronics.

The evaluation of ecological and hygienic condition of the environment was performed by ourselves in the geographical center of New Moscow--in the city of Troitsk. There was made an analysis as the published results of similar assessments in the times of the 1990s, data of Federal Service for Supervision of Consumer Rights Protection and Human Welfare concerning the control for soils quality (at a single point of the city) and drinking water for 2010-2011, and the author's materials on the chemical contamination of soils and grounds in July 2013. Local foci of moderately dangerous pollution of soil were found at lots close to the motorway and in the Worsted factory: Zc (SrBaCrVNiCoCuAgZnPbBeMoWB) = 17-20, benzo (a) pyrene to 218 mcg/kg and Zn up to 233.4 mg/kg. At the point of monitoring soils complied with the requirements according to toxicological, microbiological and parasitological characteristics.. In the drinking tap water there was observed, along with the increased total hardness, the presence up to 1.6 MAC of such natural pollutants as F and Li. In the undergrounds potable water the situation is worsening according to the content of Si, As, B, Br, U. There was no monitoring of surface water and air. However, pockets of soil contamination trace the possible occurrence in the air near the ground of hygienically dangerous anomalies of heavy metals and hydrocarbons. Modern ecological and sanitary situation in Troitsk, in general, can be considered to be quite safe if compared to the quality of the environment in industrialized cities. The thing that does cause concern is the quality of drinking water.

Analysis of the efficiency of diagnosis of lands for different functional appropriations with integral indices of chemical contamination of soils and grounds under different environmental conditions showed: the greatest accuracy of the information about the structure and degree of contamination of territories is provided by the index relying on hygienic standard (index of soil contamination, ISC). The number of hygienically dangerous lithochemical anomalies revealed by ISC is several times more than the fixed by the index of total pollution of soils by trace elements (Zc), focused only on their background levels. Index Zc is in many respects subjective and unacceptable in complex soil geochemical conditions where the selection of the regional background is impossible. ISC account not only in trace elements, but other hygienically regulated substances (As, Hg, mobile forms of metals, water-soluble salts, carbohydrates, etc.) either.

Objectives: Chemical pollution of the Amur River has seriously damaged traditions and caused posttraumatic stress disorder (PTSD) among the Nanai, the indigenous people living along this river. This study was performed to clarify the ethnographic characteristics of PTSD in this unique population., Methods: The study group consisted of 75 male and 112 female randomly selected volunteers. PTSD severity measured using scores of the Impact of Event Scale--Revised (Total-I) and Clinical-Administered PTSD Scale (Total-C) was estimated according to demographic and ethnocultural backgrounds, clinical status, and ethnopsychological attitudes toward the Amur River., Results: The differences in averages of Total-I and Total-C were not always the same in the groups divided by ethnographic information. Logistic regression analysis with a dependent variable, possibly without PTSD (Total-I <34 and Total-C <40)/possibly with PTSD (either Total-I ≥34 or Total-C ≥40), and categorical independent variables using ethnographic information extracted a low score when 'priority values' and 'the Amur River for me is' was "profession" and a high score when 'dominant role in spousal relationship' was "self," when 'predominant forms of response in stressful situations' was "try to organize," when 'preferred method of medical treatment' was specific for the Nanai, when "rely on something mystical" was manifested, and when the Amur River was believed to be "sacred"., Conclusion: Those with a pragmatic attitude were less likely to have PTSD. However, those who were required to make decisions within close relationships and were intimate with the Nanai tradition and the Amur River had increased likelihood of PTSD.

By many-body quantum-chemical calculations, we investigate the role of two structural effects--local ligand distortions and the anisotropic Cd-ion coordination--on the magnetic state of Cd(2)Os(2)O(7), a spin S = 3/2 pyrochlore. We find that these effects strongly compete, rendering the magnetic interactions and ordering crucially dependent on these geometrical features. Without trigonal distortions, a large easy-plane magnetic anisotropy develops. Their presence, however, reverses the sign of the zero-field splitting and causes a large easy-axis anisotropy (D ≃ -6.8 meV), which in conjunction with the antiferromagnetic exchange interaction (J ≃ 6.4 meV) stabilizes an all-in-all-out magnetic order. The competition uncovered here is a generic feature of pyrochlore magnets.

The analysis of the informative value of integral indicators of chemical soil contamination in the diagnosis of the status of lands used for different functional purposes has ascertained that the highest validity of information on the pattern and degree of area pollutions is achieved using by the indicator based on hygienic standards (soil pollution index (SPI)). The Xc index based on the background content of trace elements is largely subjective and unacceptable in complex soil geochemical conditions where the regional background (a railway, the Karelian Isthmus) cannot be chosen. SPI accounts for the values of not only trace elements, but also other hygienically regulated substances (As, Hg, mobile forms of metals, hydrocarbons, etc.). The quantity of hygienically dangerous lithochemical anomalies found by means of SPI is several times greater than that by means of Zc (settlements, the Volga delta).

The paper is concerned with multifactorial assessment of the air anthropogenic contamination effect on development of chronic nonspecific pulmonary diseases, chronic bronchitis (CB) in particular. Methodological approaches to identify etiological significance of anthropogenic effects in CB genesis include measurements of the air contaminants, calculation of the total contamination index, selection of the study and control territories, analysis of medical documents, conduction of wide-scale medical examinations. CB developing in the conditions of the above contamination is characterized by obstructions, bronchospastic components, other separate or systemic disorders.

A total of 126 adult patients with acute bronchitis were subjected to microbiological, virological and immunological examination. Influenza and other acute respiratory viral infections were detected in 104 (82.5%) cases of acute bronchitis. The results of microbiological examination and the study of local and systemic immunity showed that in 94.4 +/- 2.6% of the patients the development of acute bronchitis was linked with the appearance of acute pneumococcal infection irrespective of the presence, or absence, of virologically and serologically confirmed acute viral or mycoplasmal infections.