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1.
Dalton Trans ; 53(17): 7367-7375, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38591256

RESUMO

New noncentrosymmetric cerium(IV) iodate fluoride Rb2Ce(IO3)5F was prepared employing a hydrothermal technique. The compound crystallizes in the Cmc21 space group (#36) with cell parameters a = 11.1518(6) Å, b = 8.1187(4) Å and c = 17.1581(10) Å. The crystal structure of Rb2Ce(IO3)5F consists of layers composed of 8-vertex CeO7F and 7-vertex Rb(1)O7 and Rb(2)O6F polyhedra interconnected by I(2)O3 groups. These layers are stitched by trigonal pyramidal I(1)O3 and I(3)O3 groups into a 3D framework. Synthesized iodate fluoride is thermally stable in air up to 430 °C. According to DFT calculations, Rb2Ce(IO3)5F is a direct-gap semiconductor with a band gap of ca. 2.33 eV. This value is in good agreement with an estimated optical gap value of 2.35 eV. The important feature of Rb2Ce(IO3)5F is the ability to generate a second optical harmonic signal comparable to that of KH2PO4.

2.
PLoS One ; 19(2): e0298878, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38330035

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0228081.].

3.
bioRxiv ; 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38260700

RESUMO

A connection between stress-related illnesses and alcohol use disorders is extensively documented. Fear conditioning is a standard procedure used to study stress learning and links it to the activation of amygdala circuitry. However, the connection between the changes in amygdala circuit and function induced by alcohol and fear conditioning is not well established. We introduce a computational model to test the mechanistic relationship between amygdala functional and circuit adaptations during fear conditioning and the impact of acute vs. repeated alcohol exposure. In accordance with experiments, both acute and prior repeated alcohol decreases speed and robustness of fear extinction in our simulations. The model predicts that, first, the delay in fear extinction in alcohol is mostly induced by greater activation of the basolateral amygdala (BLA) after fear acquisition due to alcohol-induced modulation of synaptic weights. Second, both acute and prior repeated alcohol shifts the amygdala network away from the robust extinction regime by inhibiting the activity in the central amygdala (CeA). Third, our model predicts that fear memories formed in acute or after chronic alcohol are more connected to the context. Thus, the model suggests how circuit changes induced by alcohol may affect fear behaviors and provides a framework for investigating the involvement of multiple neuromodulators in this neuroadaptive process.

4.
Opt Express ; 31(23): 38610-38624, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017962

RESUMO

Optically Variable Devices (OVDs) are widely used as security features in anti-counterfeiting efforts. OVDs enable the display of color dynamic effects that are easily interpreted by the user. However, obtaining these elements over large areas poses certain challenges in terms of efficiency. The paper presents a modified approach for manufacturing plasmonic type OVDs through dot-matrix technology, which is a standard origination step of security holograms. By adjusting the spatial filters in the optical scheme, it is possible to double the resolution of the recorded quasi-sinusoidal diffraction gratings. The experiments confirm the creation of diffraction gratings with frequencies from 1600 to 3500 lines per mm, which facilitates the production of plasmonic zero-order spectral filters. The paper shows how the transmission characteristics of the studied elements are affected by the geometric parameters of the diffraction grating, silver layer thickness, angle of incidence, and polarization of light. The results have shown that using the proposed method it is possible to obtain 1D or 2D structural color OVD-image on a large area - several square centimeters and more. High speed recording of such elements is provided: the exposure time was from 120 to 400 ms depending on the grating resolution for a 0.05 mm2 frame, the total printing time for the size of the 25×25 mm2 OVD was about 2.5 hours for a 1D element, and less than 3.5 hours for a 2D element. Thus, the proposed method and the OVD elements produced by it can be useful to designers of optical security elements as a simpler and faster alternative to electron-beam lithographic technologies.

5.
Psychiatr Danub ; 35(Suppl 2): 141-149, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37800217

RESUMO

BACKGROUND: Post-traumatic stress disorder (PTSD) is a trauma- or stressor-related mental health condition with high socioeconomic burden. We aimed in this review to identify promising genetic markers predisposing for PTSD, which might serve in the design subsequent studies aiming to develop PTSD prevention and remediation measures. SUBJECTS AND METHODS: Our search queries in the PubMed database yielded 547 articles, of which 20 met our inclusion criteria for further analysis: published between 2018 and 2022, original research, containing molecular-genetic and statistical data, containing diagnosis verification methods, PTSD as a primary condition, and a sample of at least 60 patients. RESULTS: Among the 20 analyzed studies were reports of significant associations between PTSD and: FKBP5 variants rs9470080, regardless of the C or T allele; two FKBP5 haplotypes (A-G-C-C and A-G-C-T); gene-gene DRDхANNK1-COMT (rs1800497 × rs6269) and OXTR-DRD2 (rs2268498 × rs1801028); C-allele of CRHR1 (rs1724402). Other findings, such as the association of FKBP5 haplotypes (A-G-C-C, A-G-C-T) and the FKBP5-CRHR1 genotype, were of lesser statistical significance and less extensively studied. CONCLUSIONS: Although our literature analysis implicates certain genetic factors in PTSD, our understanding of the polygenic nature underlying the disorder remains limited, especially considering the hitherto underexplored epigenetic mechanisms. Future research endeavors should prioritize exploring these aspects to provide a more nuanced understanding of PTSD and its genetic underpinnings.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/genética , Transtornos de Estresse Pós-Traumáticos/prevenção & controle , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Haplótipos , Polimorfismo de Nucleotídeo Único , Genótipo , Alelos
6.
Psychiatr Danub ; 35(Suppl 2): 322-328, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37800249

RESUMO

BACKGROUND: Spinal muscular atrophy (SMA) is a rare genetic disorder, in which, for the common childhood onset forms, loss of function of the SMA 5q gene leads to disability and death before adulthood. Symptomatic treatment focusses on respiratory and nutritional support, and physical therapy, but there is little consideration of psychiatric manifestations of SMA. The aim of this study was to explore blood biomarker levels, electromyography (EMG) data, and clinical manifestations, including psychiatric impairments, in patients with SMA 5q. Our objectives were twofold: First, to assess the clinical relevance of standard biomarkers, i.e., creatinine, creatine kinase (CK), and lactate dehydrogenase (LDH) levels, and second, to obtain data supporting the development of an effective prognostic algorithm for the course of this disease. RESULTS: We analyzed retrospective data from 112 medical records of 58 registered patients (2008-2022) with SMA. At the time of last registration, the 58 patients had a mean age 38.4 years [13.68; 55.0], of whom 32 (52%) were female. The subgroup of 21 pediatric patients had a mean age 12.32 years [6.57; 13.93], of whom 14 (24%) were girls. The ICD-10 diagnoses were as follows: G12.0 (n=7, 12%, children), G12.1 (n=14, 24% children; n=29, 50% adults), G12.8 (n=6, 10% adults), G12.9 (n=2, 1% adults). The archival data on psychiatric status indicated emotional lability (n=6, 10.3%), fatigue (n=10, 17.2%), and tearfulness (n=3, 5.2%) in some patients. There were no significant subgroup differences in serum creatinine and CK levels, but there were significant differences in LDH levels between the G12.0, G12.1, G12.8, and G12.9 subgroups. Among the serum biomarkers, only LDH levels showed significant differences among the subgroups of SMA 5q patients; higher levels in the G12.1, G12.8, and G12.9 groups compared to the G12.0 (infantile) group related to age, weight, gender, and level of physical activity. Data on psychiatric status were insufficient to identify group differences and associations with biomarker levels. Likewise, longitudinal data on repeat hospitalizations did not indicate associations with biomarker levels. CONCLUSIONS: Creatinine, CK, and LDH levels were insufficient for monitoring and predicting the course of SMA. Further prospective research is needed to elaborate the weak relationships between CK levels, the dynamics of the clinical presentation, and therapeutic interventions, and to investigate psychiatric co-morbidities in SMA 5q patients.


Assuntos
Atrofia Muscular Espinal , Adulto , Humanos , Criança , Feminino , Masculino , Estudos Retrospectivos , Creatinina/uso terapêutico , Atrofia Muscular Espinal/tratamento farmacológico , Exercício Físico , Biomarcadores
7.
Dalton Trans ; 52(33): 11611-11620, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37551451

RESUMO

New quaternary compounds RE2Co2AlC (RE = La, Pr, Nd) of the filled W2CoB2 structure type were synthesized by the reaction of samples with the nominal composition RE40Co40Al20 (RE = La, Pr, Nd) and carbon. Single crystal X-ray diffraction data show that the RE2Co2AlC compounds crystallize in a body-centered orthorhombic space group Immm (oI12) with Z = 2 and a = 4.1841(11) Å, b = 6.1161(15) Å, c = 9.091(2) Å (La2Co2AlC); a = 4.1290(9) Å, b = 6.1152(18) Å, c = 8.844(3) Å (Pr2Co2AlC); a = 4.1168(15) Å, b = 6.1131(17) Å, c = 8.792(5) Å (Nd2Co2AlC) and are isotypic to the recently reported Nd2Co2SiC. The structures can be described as interstitial carbides of the W2CoB2 structure type with carbon atoms fully occupying the octahedral voids, which leads to the anisotropic expansion of the unit cell, more pronounced along the b-axis. Electronic structure calculations predict the RE2Co2AlC (RE = La, Pr, Nd) compounds to be metallic. The relative stability of the La2Co2AlX structures where X = C, O, Si, or a vacancy was investigated based on the bonding analysis, which emphasizes the important role that carbon plays in stabilizing the structural motif.

8.
Opt Lett ; 48(13): 3603-3606, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390191

RESUMO

Femtosecond inscription of fiber Bragg gratings (FBGs) in each core of a cladding-pumped seven-core Yb-doped fiber enables efficient (≈70%) 1064-nm lasing in a robust all-fiber scheme with ≈33 W power, nearly the same for uncoupled and coupled cores. However, the output spectrum is quite different: without coupling, seven individual lines corresponding to the in-core FBG reflection spectra sum up into a broad (0.22 nm) total spectrum, whereas the multiline spectrum collapses into a single narrow line at strong coupling. The developed model shows that the coupled-core laser generates coherent superposition of supermodes at the wavelength corresponding to the geometric mean of the individual FBG spectra, whereas the generated laser line broadens, with a power (0.04-0.12 nm) like the single-core mode of a seven-times larger effective area.

9.
Small ; 19(28): e2301660, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37178371

RESUMO

Emerging technologies for integrated optical circuits demand novel approaches and materials. This includes a search for nanoscale waveguides that should satisfy criteria of high optical density, small cross-section, technological feasibility and structural perfection. All these criteria are met with self-assembled gallium phosphide (GaP) epitaxial nanowires. In this work, the effects of the nanowire geometry on their waveguiding properties are studied both experimentally and numerically. Cut-off wavelength dependence on the nanowire diameter is analyzed to demonstrate the pathways for fabrication of low-loss and subwavelength cross-section waveguides for visible and near-infrared (IR) ranges. Probing the waveguides with a supercontinuum laser unveils the filtering properties of the nanowires due to their resonant action. The nanowires exhibit perfect elasticity allowing fabrication of curved waveguides. It is demonstrated that for the nanowire diameters exceeding the cut-off value, the bending does not sufficiently reduce the field confinement promoting applicability of the approach for the development of nanoscale waveguides with a preassigned geometry. Optical X-coupler made of two GaP nanowires allowing for spectral separation of the signal is fabricated. The results of this work open new ways for the utilization of GaP nanowires as elements of advanced photonic logic circuits and nanoscale interferometers.

10.
PLoS One ; 18(3): e0279841, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36943842

RESUMO

Cortical and basal ganglia circuits play a crucial role in the formation of goal-directed and habitual behaviors. In this study, we investigate the cortico-striatal circuitry involved in learning and the role of this circuitry in the emergence of inflexible behaviors such as those observed in addiction. Specifically, we develop a computational model of cortico-striatal interactions that performs concurrent goal-directed and habit learning. The model accomplishes this by distinguishing learning processes in the dorsomedial striatum (DMS) that rely on reward prediction error signals as distinct from the dorsolateral striatum (DLS) where learning is supported by salience signals. These striatal subregions each operate on unique cortical input: the DMS receives input from the prefrontal cortex (PFC) which represents outcomes, and the DLS receives input from the premotor cortex which determines action selection. Following an initial learning of a two-alternative forced choice task, we subjected the model to reversal learning, reward devaluation, and learning a punished outcome. Behavior driven by stimulus-response associations in the DLS resisted goal-directed learning of new reward feedback rules despite devaluation or punishment, indicating the expression of habit. We repeated these simulations after the impairment of executive control, which was implemented as poor outcome representation in the PFC. The degraded executive control reduced the efficacy of goal-directed learning, and stimulus-response associations in the DLS were even more resistant to the learning of new reward feedback rules. In summary, this model describes how circuits of the dorsal striatum are dynamically engaged to control behavior and how the impairment of executive control by the PFC enhances inflexible behavior.


Assuntos
Gânglios da Base , Corpo Estriado , Corpo Estriado/fisiologia , Gânglios da Base/fisiologia , Neostriado , Motivação , Reversão de Aprendizagem , Recompensa
11.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 79(Pt 2): 176-183, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36920872

RESUMO

Compounds with the general formula Ln3+(SeO3)(HSeO3)·2H2O, where Ln = Sm3+, Tb3+, Nd3+ and Lu3+, are characterized by orthorhombic symmetry with space group P212121 and unit-cell parameters in the ranges a ∼ 6.473-6.999, b ∼ 6.845-7.101, c ∼ 16.242-16.426 Å. Light-purple irregularly shaped crystals of a new monoclinic polytype of neodymium selenite Nd(SeO3)(HSeO3)·2H2O have been obtained during a mild-condition hydrothermal synthesis. The monoclinic unit-cell parameters are: a = 7.0815 (2), b = 6.6996 (2), c = 16.7734 (5) Å, ß = 101.256 (1)°, V = 780.48 (6) Å3; space group P21/c. The crystal structures of Nd(SeO3)(HSeO3)·2H2O polymorphs show order-disorder (OD) character and can be described using the same OD groupoid family, more precisely a family of OD structures built up from two kinds of non-polar layers (category IV). The first monoclinic maximum degree order (MDO) structure (MDO1-polytype) with space group P21/c can be obtained when the inversion centre is active in the L2n-type layers, while the second MDO structure (MDO2-polytype) is orthorhombic with space group P212121 and can be obtained when the [21--] operation is active in the L2n-type layers. The structural complexity parameters and DFT calculations of both polytypes show that the polytype structures are extremely close energy-wise and almost equally viable from the point of total energy of the structure.

12.
Int J Mol Sci ; 24(3)2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36768523

RESUMO

In searching for a tool for optimizing the band gap of a hybrid compound capable of serving as a light-harvesting material in lead-free photovoltaics, we synthesized a new polyiodoantimonate (HpipeH2)2[Sb2I10](I2) and analyzed its crystal and electronic structure by application of X-ray crystal structure analysis, Raman and diffuse reflectance spectroscopies, and quantum chemical calculations. It was demonstrated that I2 molecules link Sb2I10 edge-sharing octahedra into zig-zag chains, whereas the organic cations link inorganic anionic chains into a 3D structure featuring a complex pattern of covalent bonds and non-covalent interactions. Overall, these features provide the background for forming the electronic structure with a narrow band gap of 1.41 eV, therefore being a versatile tool for optimizing the band gap of a potential light-harvesting hybrid compound.


Assuntos
Eletrônica , Polímeros , Ânions , Sorogrupo
13.
Nanoscale ; 15(5): 2332-2339, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36637064

RESUMO

Semiconductor nanowires are the perfect platform for nanophotonic applications owing to their resonant, waveguiding optical properties and technological capabilities providing control over their crystalline and chemical compositions. The vapor-liquid-solid growth mechanism allows the formation of hybrid metal-dielectric nanostructures promoting sub-wavelength light manipulation. In this work, we explore both experimentally and numerically the plasmonic effects promoted by a gallium (Ga) nanoparticle optical antenna decorating the facet of gallium phosphide (GaP) nanowires. Raman, photoluminescence and near-field mapping techniques are used to study the effects. We demonstrate several phenomena including field enhancement, antenna effect and increase in internal reflection. We show that the observed effects have to be considered when nanowires with a plasmonic particle are used in nanophotonic circuits and discuss the ways for utilization of these effects for efficient coupling of light into nanowire waveguide and field tailoring. The results open up promising pathways for the development of both passive and active nanophotonic elements, light harvesting and sensorics.

14.
Sci Rep ; 12(1): 21904, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36535983

RESUMO

All-dielectric nanophotonics opens a venue for a variety of novel phenomena and scattering regimes driven by unique optical effects in semiconductor and dielectric nanoresonators. Their peculiar optical signatures enabled by simultaneous electric and magnetic responses in the visible range pave a way for a plenty of new applications in nano-optics, biology, sensing, etc. In this work, we investigate fabrication-friendly truncated cone resonators and achieve several important scattering regimes due to the inherent property of cones-broken symmetry along the main axis without involving complex geometries or structured beams. We show this symmetry breaking to deliver various kinds of Kerker effects (generalized and transverse Kerker effects), non-scattering hybrid anapole regime (simultaneous anapole conditions for all the multipoles in a particle leading to the nearly full scattering suppression) and, vice versa, superscattering regime. Being governed by the same straightforward geometrical paradigm, discussed effects could greatly simplify the manufacturing process of photonic devices with different functionalities. Moreover, the additional degrees of freedom driven by the conicity open new horizons to tailor light-matter interactions at the nanoscale.

15.
Dalton Trans ; 51(48): 18583-18592, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36444887

RESUMO

Three quaternary phosphide platinides, Ca2Pt7AlP3.00(4), Ca2Pt7TiP3.24(4), and Ca2Pt7ZnP2.78(2), were synthesized by a high-temperature technique using lead as a flux. According to the single-crystal diffraction data, they are isotypic and crystallize in the tetragonal space group I4/mmm with Z = 2 (Ca2Pt7AlP3.00(4): a = 3.9893(6) Å, c = 26.832(5) Å; Ca2Pt7TiP3.24(4): a = 3.99610(10) Å, c = 26.9074(17) Å; Ca2Pt7ZnP2.78(2): a = 4.0020(2) Å, c = 26.5549(17) Å) and thus represent first europium-free compounds of the Eu2Pt7AlP2.95 structure type. Their structures can be described as an intergrowth of the AuCu3- and CaBe2Ge2-type blocks. DFT calculations predict metallic conductivity and non-magnetic state for all three compounds. Bonding analysis based on the Bader charge distribution and ELF topology reveals a combination of localized covalent and ionic interactions in the CaBe2Ge2-type fragments and complex pattern of pairwise, multi-center, and ionic interactions in the AuCu3-type fragments that closely reproduces bonding in the parent Pt3X (X = Al, Ti, Zn) binary intermetallics.

16.
Inorg Chem ; 61(24): 9173-9183, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35670830

RESUMO

Using a high-temperature ampoule technique and lead metal as a flux, we have grown single crystals and determined crystal structures from single-crystal X-ray diffraction data of two metal-rich phosphides, Sr5Pt12P9 (P 21/m, a = 6.1472(3) Å, b = 25.1713(13) Å, c = 6.4635(3) Å, ß = 99.604(2)°, Z = 2, R1 = 0.0326, wR2 = 0.0786) and BaPt3P2 (P 212121, a = 6.3605(6) Å, b = 6.8541(7) Å, c = 11.3493(12) Å, Z = 4, R1 = 0.0231, wR2 = 0.0501). Both compounds belong to their own structure types and feature 3D networks of Pt and P atoms, with the channels occupied by alkaline earth metal cations. Density functional theory calculations reveal Sr5Pt12P9 to be a metal, while BaPt3P2 is a narrow-gap semiconductor with a band gap of 0.24 eV. Bonding analysis shows that both compounds feature networks of prominent covalent localized Pt-P bonds, responsible for their structural stability, as well as additional weaker and, likely, less localized Pt-Pt interactions.

17.
Opt Lett ; 47(5): 1222-1225, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35230332

RESUMO

All-fiber Raman lasers have demonstrated their potential for efficient conversion of highly multimode pump beams into high-quality Stokes beams. However, the modal content of these beams has not yet been investigated. In this work, based on a mode decomposition technique, we are able to reveal the details of intermodal interactions in the different operation regimes of continuous wave multimode graded-index fiber Raman lasers. We observed that, above the laser threshold, the residual pump beam is strongly depleted in its transverse modes with principal quantum number below 10. However, the generated Stokes signal beam mainly consists of the fundamental mode, but higher-order modes are also present, albeit with exponentially decreasing population.

18.
Opt Express ; 30(5): 8212-8221, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35299567

RESUMO

We develop a comprehensive theory for describing the experimental beam profiles from multimode fiber Raman lasers. We take into account the presence of random linear mode coupling, Kerr beam self-cleaning and intra-cavity spatial filtering. All of these factors play a decisive role in shaping the Stokes beam, which has a predominant fundamental mode content. Although the highly multimode pump beam is strongly depleted, it remains almost insensitive to the different physical effects. As a result, the intensity of the output Stokes beam is an order of magnitude higher than the pump intensity at its maximum, in quantitative agreement with the experimental results and in contrast with the simplified balance model.

19.
Nanomaterials (Basel) ; 12(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35055259

RESUMO

Tailorable synthesis of axially heterostructured epitaxial nanowires (NWs) with a proper choice of materials allows for the fabrication of novel photonic devices, such as a nanoemitter in the resonant cavity. An example of the structure is a GaP nanowire with ternary GaPAs insertions in the form of nano-sized discs studied in this work. With the use of the micro-photoluminescence technique and numerical calculations, we experimentally and theoretically study photoluminescence emission in individual heterostructured NWs. Due to the high refractive index and near-zero absorption through the emission band, the photoluminescence signal tends to couple into the nanowire cavity acting as a Fabry-Perot resonator, while weak radiation propagating perpendicular to the nanowire axis is registered in the vicinity of each nano-sized disc. Thus, within the heterostructured nanowire, both amplitude and spectrally anisotropic photoluminescent signals can be achieved. Numerical modeling of the nanowire with insertions emitting in infrared demonstrates a decay in the emission directivity and simultaneous rise of the emitters coupling with an increase in the wavelength. The emergence of modulated and non-modulated radiation is discussed, and possible nanophotonic applications are considered.

20.
Inorg Chem ; 61(1): 568-578, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34932353

RESUMO

Transition metal-based endohedral cluster intermetallic compounds are interesting electron phases, which frequently exhibit superconductivity with a peculiar interplay between the critical temperature and valence electron count. We present a new Re-based endohedral gallium cluster compound, Re2Ga9Ge. Its unique crystal structure (P42/mmc space group, a = 8.0452(3) Å, c = 6.7132(2) Å) is built by two types of gallium polyhedra: monocapped Archimedean antiprisms centered by rhenium atoms and tetrahedra containing a main-group element inside. The analysis of chemical bonding shows the presence of localized pairwise interactions between the p-block elements and the formation of multicenter bonds with the participation of d-orbitals of rhenium. In the electronic band structure, the Fermi level is located in a narrow pseudogap indicating the optimum band filling and thus explaining the virtual absence of a homogeneity range. The compound exhibits Pauli paramagnetism and metallic properties with unexpectedly low thermal conductivity. A sharp anomaly observed on the magnetic susceptibility and resistivity curves presumably indicates the electronic phase transition accompanied by charge ordering at the characteristic temperature of T * = 271 K in zero magnetic field.

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