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We report the synthesis, ESR spectroscopic and spin coherent properties of the dimetallofullerene Sc2@C80(CH2Ph). The single-electron metal–metal bond of the Sc2 dimer inside the fullerene's cage is stabilized with the electron spin density being fully localized at the metal bond. This results in an extraordinary strong hyperfine interaction of the electron spin with the 45Sc nuclear spins with a coupling constant a = 18.2 mT (∼510 MHz) and yields a fully resolved hyperfine-split ESR spectrum comprising 64 lines. The splitting is present even at low temperatures where the molecular dynamics are completely frozen. The large extent and the robustness of the hyperfine-split spectra enable us to identify and control the well-defined transitions between specific electron-nuclear quantum states. This made it possible to demonstrate in our pulse ESR study the remarkable spin coherent dynamics of Sc2@C80(CH2Ph), such as the generation of arbitrary superpositions of the spin states in a nutation experiment and the spin dephasing times above 10 μs at temperatures T < 80 K reaching the value of 17 μs at T ≤ 20 K. These observations suggest Sc2@C80(CH2Ph) as an interesting qubit candidate and motivate further synthetic efforts to obtain fullerene-based systems with superior spin properties.

Optical Tweezers (OTs) is not only a novelty in laser physics but also an indispensable tool in cell biology studies, especially in the precise manipulation of single living cells and detection of ultra-low intercellular bio-forces. The reversible aggregation of red blood cells (RBCs) strongly influences the blood rheological properties and is critical for blood microcirculation monitoring and therapy. However, the mechanism behind and the factors influencing the aggregation dynamics are still not clear. In this study, the peculiarity of red blood cell interaction was investigated and the potential factors influencing the aggregation process were clarified by optical tweezers. The intercellular interaction force in cell pairs, the role of cell deformation and adhesion time in interaction dynamics, as well as the effects of low-level laser irradiation, were evaluated and discussed.

Detailed electronic structure of single atomic magnets is a crucial bit in the further understanding and design of a new generation of monoatomic magnetic elements on surfaces and in molecules. Control and manipulation of the single atomic state, as well as long relaxation of magnetization, have been demonstrated for lanthanide atoms on carefully chosen supporting substrates. However, these convincing experiments are puzzling by insufficient theoretical description, usually omitting the valence electrons of lanthanide atoms. In this work, starting with an idea of the inevitable need of local d- and p-shell electrons for a proper description of the magnetic states of lanthanide atoms, we rationalized the electronic structure and magnetic properties of Ho atom on the MgO substrate using ab initio multiconfigurational approaches. By doing so, we obtained the solution which complements experimental observations without any assumptions and has been able to pin-point the atomic state which most likely to be responsible for the exceptional magnetic properties of Ho on MgO. This study demonstrates that new paradigms are needed for understanding and interpretation of the lanthanide single-atomic magnets.

We report the first successful synthesis of a CF

Magnetic hysteresis is a direct manifestation of nonequilibrium physics that has to be understood if a system is to be used for information storage and processing. The dilanthanide endofullerene ${\mathrm{Tb}}_{2}\mathrm{ScN}@{\mathrm{C}}_{80}$ is shown to be a single-molecule magnet with a remanence time on the order of 100 s at 400 mK. Three different temperature-dependent relaxation barriers are discerned. The lowest 1 K barrier is assigned to intermolecular dipole-dipole interaction, the 10 K barrier to intramolecular exchange and dipolar coupling, and the 50 K barrier to molecular vibrations as was observed for ${\mathrm{Dy}}_{2}\mathrm{ScN}@{\mathrm{C}}_{80}$. The 4 orders of magnitude difference in the prefactor between the Tb and the Dy compound in the decay process across the 10 K barrier is assigned to the lack of Kramers protection in ${\mathrm{Tb}}^{3+}$. The sub-Kelvin hysteresis follows changes in the magnetization at level crossings of the four possible ${\mathrm{Tb}}_{2}$ ground-state configurations. Comparison to a hysteresis model, with magnetic relaxation at level crossings only, reveals cooperative action between nearby molecules.

The formation of ferrocenyl-functionalized iron and cobalt carbonyl clusters is reported, based on a reaction of FcPCl

Pancreatic ductal adenocarcinoma (PDAC) remains a disease with extremely poor prognosis and limited effective available treatment. Differential expression of miRNAs isolated from tumor tissue has been proposed as a marker for tumor diagnosis, progression, and prognosis. Nevertheless, the prognostic value of miRNAs expression in PDACs for patient outcome still remains unclear. Expression of 7 selected miRNAs, isolated from FFPE samples of 54 PDAC patients, was quantified using RT-qPCR. The relationship of miRNA expression levels with tumor histology, clinicopathological characteristics, patient overall survival (OS), and progress-free survival (PFS), was subsequently evaluated. Overexpression of miR-21, miR-155, and miR-210 was observed in PDACs (up to 72.62, 232.36, and 181.38-fold, respectively), in comparison with non-neoplastic tissues. On the other hand, miR-96 and miR-217 were significantly downregulated in PDACs (up to one hundred times). No differences were, however, noticed between cancer and normal tissues for the expression levels of miR-148a and miR-196a. On the other hand, expression levels of all 7 miRNAs failed to demonstrate a significant correlation with parameters of tumor progression, such as tumor stage, grade, nodal involvement, perineural, and vascular invasion. The positive correlation of miR-210 levels was, however, observed with patient age (ρ=0.35). Additionally, miR-148a and miR-217 expressions have shown a positive association with tubular tumor growth pattern (ρ=0.39; ρ=0.28). The negative correlation of miR-148a values was also demonstrated with dissociative growth pattern and nuclear atypia (ρ=-0.30; ρ=-0.27). Finally, no statistically significant correlation could be demonstrated with the expression levels of all 7 tested miRNAs and PDAC patient survival; neither for OS nor for PFS (p>0.05). Our data have confirmed abnormal miRNAs expression in PDACs in comparison with adjacent non-neoplastic tissue. On the other hand, no correlation was discovered between miRNA expression and parameters of tumor progression. We have found a significant association between histologic tumor growth patterns and miRNA expression, making this work the first study, which analyses this aspect of PDAC. Finally, in our group of patients, no relationship of miRNA levels and patient prognosis could be demonstrated. Therefore, further investigation is required to evaluate the predictive and prognostic potential of miRNAs in a clinical setting.

Reversibly switching the light absorption of organic molecules by redox processes is of interest for applications in sensors, light harvesting, smart materials, and medical diagnostics. This work presents a symmetrical benzothiadiazole (BTD) derivative with a high fluorescence quantum yield in solution and in the crystalline state and shows by spectroelectrochemical analysis that reversible switching of UV absorption in the neutral state, to broadband Vis/NIR absorption in the 1st oxidized state, to sharp band Vis absorption in the 2nd oxidized state, is possible. For the one‐electron oxidized species, formation of a delocalized radical is confirmed by electron paramagnetic resonance spectroelectrochemistry. Furthermore, our results reveal an increasing quinoidal distortion upon the 1st and 2nd oxidation, which can be used as the leitmotif for the development of BTD based redox switches., The quinoidial distortion induced in benzothidiazoles upon oxidation was used in this work to design an absorption redox switch. Using spectroelectrochemical analysis, the absorption, fluorescence and localization of the radical were investigated during the redox processes. The symmetrical benzothiadiazole derivative can thus be used as a UV to Vis/NIR absorption switch or as a fluorescence ON/OFF switch. With deeper understanding of the quinodial distortion, it can furthermore be used as the basis for development of other small organic redox switches.

In this paper we prove that if S is a set of operators acting on a separable L p -space X, 1 ≤ p < ∞ (or, more generally, on any separable Kothe function space) such that S is indecomposable (that is, no non-trivial subspace of X of the form L p (A), where A is measurable, is a common S-invariant subspace), then $$\overline {span} $$ S admits an indecomposable operator. As applications, we obtain some new results about transitive algebas on separable Hilbert spaces, as well as an extension of the simultaneous Wielandt theorem to semigroups of operators acting on separable L p -spaces.

Relaxation of magnetization in endohedral metallofullerenes DySc2N@C80 is studied at different temperatures, in different magnetic fields, and in different molecular arrangements. Magnetization behavior and relaxation are analyzed for powder sample, and for DySc2N@C80 diluted in non-magnetic fullerene Lu3N@C80, adsorbed in voids of a metal–organic framework, and dispersed in a polymer. The magnetic field dependence and zero-field relaxation are also studied for single-crystals of DySc2N@C80 co-crystallized with Ni(II) octaethylporphyrin, as well as for the single crystal diluted with Lu3N@C80. Landau–Zener theory is applied to analyze quantum tunneling of magnetization in the crystals. The field dependence of relaxation rates revealed a dramatic dependence of the zero-field tunneling resonance width on the dilution and is explained with the help of an analysis of dipolar field distributions. AC magnetometry is used then to get access to the relaxation of magnetization in a broader temperature range, from 2 to 87 K. Finally, a theoretical framework describing the spin dynamics with dissipation is proposed to study magnetization relaxation phenomena in single molecule magnets.

Carbide clusterfullerene DyYTiC@C80-Ih with three different metal atoms in the endohedral cluster is obtained by arc-discharge synthesis with methane as reactive gas and is successfully isolated by HPLC. The compound shows single-molecule magnetism (SMM) with magnetic hysteresis below 8 K. The SMM properties of DyYTiC@C80 are compared to those of DySc2N@C80 and the influence of the central atom in the endohedral cluster is analyzed.

The magnetic ordering and bistability of one-dimensional chains of endofullerene Dy2ScN@C80 single-molecule magnets (SMMs) packed inside single-walled carbon nanotubes (SWCNTs) have been studied using high-resolution transmission electron microscopy (HRTEM), X-ray magnetic circular dichroism (XMCD), and ab initio calculations. X-ray absorption measurements reveal that the orientation of the encapsulated endofullerenes differs from the isotropic distribution in the bulk sample, indicating a partial ordering of the endofullerenes inside the SWCNTs. The effect of the one-dimensional packing was further investigated by ab initio calculations, demonstrating that for specific tube diameters, the encapsulation is leading to energetically preferential orientations of the endohedral clusters. Additionally, element-specific magnetization curves reveal a decreased magnetic bistability of the encapsulated Dy2ScN@C80 SMMs compared to the bulk analog.

Assembly of bimetallic complexes on boron clusters by coordination of coinage metal cations to Ru–B single bonds., In this work, we introduce a novel approach for the selective assembly of heterometallic complexes by unprecedented coordination of coinage metal cations to strained single ruthenium–boron bonds on a surface of icosahedral boron clusters. M(i) cations (M = Cu, Ag, and Au) insert into B–Ru bonds of the (BB)–carboryne complex of ruthenium with the formation of four-membered B–M–Ru–B metalacycles. Results of theoretical calculations suggest that bonding within these metalacycles can be best described as unusual three-center-two-electron B–M···Ru interactions that are isolobal to B–H···Ru borane coordination for M = Cu and Ag, or the pairs of two-center-two electron B–Au and Au–Ru interactions for M = Au. These transformations comprise the first synthetic route to exohedral coinage metal boryl complexes of icosahedral closo-{C2B10} clusters, which feature short Cu–B (2.029(2) Å) and Ag–B (2.182(3) Å) bonds and the shortest Au–B bond (2.027(2) Å) reported to date. The reported heterometallic complexes contain Cu(i) and Au(i) centers in uncharacteristic square-planar coordination environments. These findings pave the way to rational construction of a broader class of multimetallic architectures featuring M–B bonds.

Two series of aromatic compounds with perfluoroalkyl (RF ) groups of increasing length, 1,3,5,7-naphthalene(RF )4 and 1,3,5,7,9-corannulene(RF )5 , have been prepared and their electronic properties studied by low-temperature photoelectron spectroscopy (PES) (for gas-phase electron affinity measurements). These and many related compounds were also studied by DFT calculations. The data demonstrate unambiguously that the electron-withdrawing ability of RF substituents increases significantly and uniformly from CF3 to C2 F5 to n-C3 F7 to n-C4 F9 .

Endohedral fullerene Y3N@C80 exhibits luminescence with reasonable quantum yield and extraordinary long lifetime. By variable-temperature steady-state and time-resolved luminescence spectroscopy, we demonstrate that above 60 K the Y3N@C80 exhibits thermally-activated delayed fluorescence with maximum emission at 120 K and a negligible prompt fluorescence. Below 60 K, a phosphorescence with a lifetime of 192 ms is observed. Spin distribution and dynamics in the triplet excited state is investigated with X- and W-band EPR and ENDOR spectroscopies and DFT computations. Finally, electroluminescence of the Y3N@C80/PFO film is demonstrated opening the possibility for red-emitting fullerene-based organic light-emitting diodes (OLEDs).

The endohedral fullerene Y3N@C80 exhibits luminescence with reasonable quantum yield and extraordinary long lifetime. By variable‐temperature steady‐state and time‐resolved luminescence spectroscopy, it is demonstrated that above 60 K the Y3N@C80 exhibits thermally activated delayed fluorescence with maximum emission at 120 K and a negligible prompt fluorescence. Below 60 K, a phosphorescence with a lifetime of 192±1 ms is observed. Spin distribution and dynamics in the triplet excited state is investigated with X‐ and W‐band EPR and ENDOR spectroscopies and DFT computations. Finally, electroluminescence of the Y3N@C80/PFO film is demonstrated opening the possibility for red‐emitting fullerene‐based organic light‐emitting diodes (OLEDs).

Herein, we report the design and synthesis of a series of novel cationic nitrogen-doped nanographenes (CNDNs) with nonplanar geometry and axial chirality. Single-crystal X-ray analysis reveals helical and cove-edged structures. Compared to their all-carbon analogues, the frontier orbitals of the CNDNs are energetically lower lying, with a reduced optical energy gap and greater electron-accepting behavior. Cyclic voltammetry shows all the derivatives to undergo quasireversible reductions. In situ spectroelectrochemical studies prove that, depending on the number of nitrogen dopants, either neutral radicals (one nitrogen dopant) or radical cations (two nitrogen dopants) are formed upon reduction. The concept of cationic nitrogen doping and introducing helicity into nanographenes paves the way for the design and synthesis of expanded nanographenes or even graphene nanoribbons with cationic nitrogen dopants.

Wir berichten uber Design und Synthese einer Serie von neuen kationischen stickstoffdotierten Nanographenen (CNDN) mit einer nichtplanaren Geometrie und axialer Chiralitat. Einkristall-Rontgendiffraktometrie beweist deren helikale und teils “Cove”-terminierte Struktur. Verglichen mit den reinen Kohlenstoffanalogen liegen die Grenzorbitale der CNDN energetisch tiefer, was zu einer verringerten optischen Energielucke und einer erhohten Elektronenaffinitat fuhrt. Alle Derivate zeigen in cyclovoltammetrischen Untersuchungen quasireversibles Reduktionsverhalten. Abhangig von der Zahl an Stickstoffdotanden ist es moglich, neutrale Radikale (bei einem Stickstoffdotanden) oder Radikalkationen (bei zwei Stickstoffdotanden) wahrend des Reduktionsprozesses uber In-situ-Spektroelektrochemie zu analysieren. Kationische Stickstoffdotierung kombiniert mit Helizitat erschliest neue Wege fur das Design und die Synthese von ausgedehnten Nanographenen und Nanographenstreifen.

Interplay between the encapsulated cluster and fullerene cage is crucial for the stability of endohedral clusterfullerene. Herein we report the synthesis and isolation of a new entrant of carbido clusterfullerene, TiTb2C@Ih(7)-C80. The molecular structure of TiTb2C@Ih(7)-C80 was determined unambiguously by single crystal X-ray diffraction, featuring a pyramidal TiTb2C cluster encapsulated within the popular Ih(7)-C80 cage. To our knowledge, TiTb2C represents the first pyramidal cluster found for carbido clusterfullerenes. On the basis of a comparative study with the reported TiM2C@Ih(7)-C80 (M = Sc, Lu) carbido clusterfullerenes and M3N@Ih(7)-C80 (M = Sc, Y and lanthanide) nitride clusterfullerenes, we tentatively determined the borderline of the sum of the three M-C(N) bond lengths of M3N/C for the encapsulated M3N/C cluster changing from planar to pyramidal geometry as 6.15–6.20 A. The electrochemical analyses on TiM2C@Ih(7)-C80 unraveled the self-adaptive structural transformations existing in the TiM2C@Ih(7)-C80 (M = Er, Y, Dy and Tb) based on their similar cluster-cage strain evaluated through electrochemical measurements.

A new redox conducting polymer, viz. poly[meso-N,N′-bis(salicylidene)-2,3-butanediaminonickel(II)], poly[meso-Ni(II)-SaldMe], belonging to the Schiff base polymer family, was electrochemically synthesized. The charge transfer and polymerization mechanism were unraveled by simultaneous cyclic voltammetry (CV) and in situ UV–vis, FTIR-ATR, and ex situ low-temperature ESR spectroscopy. With the latter, a short-living paramagnetic transient form of electro-oxidized poly[meso-Ni(II)-SaldMe] was detected. This form was identified as the bisphenolic radical cation. In situ UV–vis and FTIR-ATR spectroelectrochemistry measurements revealed that the charge transfer of the polymer involved bisphenolic radical cation formation at the potential lower than 0.80 V vs Ag/Ag+ and then dication formation at the potential exceeding 0.80 V. The proposed mechanism of electropolymerization of meso-N,N′-bis(salicylidene)-2,3-butanediaminonickel(II), meso-Ni(II)-SaldMe, involves two steps. First, electro-oxidation of the monomer...

Synthesis of antiaromatic polycyclic hydrocarbons (PHs) is challenging because the high energy of their highest occupied molecular orbital and low energy of their lowest unoccupied molecular orbital cause them to be reactive and unstable. In this work, two large antiaromatic acene analogues, namely, cyclopenta[pqr]indeno[2,1,7-ijk]tetraphene (CIT, 1a) and cyclopenta[pqr]indeno[7,1,2-cde]picene (CIP, 1b), as well as a curved antiaromatic molecule with 48 π-electrons, dibenzo[a,c]diindeno[7,1,2-fgh:7',1',2'-mno]phenanthro[9,10-k]tetraphene (DPT, 1c), are synthesized on the basis of the corona of indeno[1,2-b]fluorene. These three antiaromatic PHs possess a narrow energy gap down to 1.55 eV and exhibit high kinetic stability under ambient conditions. Moreover, these compounds display reversible electron transfer processes in both the cathodic and anodic regimes. Their cation and anion radicals are characterized by in situ vis-NIR absorption and electron paramagnetic resonance spectroelectrochemistry. The X-ray crystallographic analysis confirms that while CIP and CIT manifest planar structures, DPT shows a curved π-conjugated carbon skeleton. The synthetic strategy starting from ortho-substituted benzene units to construct five-membered rings in this work provides a unique entry to novel pentagon-embedding or curved antiaromatic polycyclic hydrocarbons. In addition, besides the detailed chemical and physical investigations, microscale single-crystal fiber field-effect transistors were also fabricated.

We performed a study on the fundamental adsorption characteristics of Er3N@C80 deposited on W(110) and Au(111) via room temperature scanning tunneling microscopy and spectroscopy. Adsorbed on W(110), a comparatively strong bond to the endohedral fullerenes inhibited the formation of ordered monolayer islands. In contrast, the Au(111)-surface provides a sufficiently high mobility for the molecules to arrange in monolayer islands after annealing. Interestingly, the fullerenes modify the herringbone reconstruction indicating that the molecule–substrate interaction is of considerable extent. Investigations concerning the electronic structure of Er3N@C80/Au(111) reveals spatial variations dependent on the termination of the Au(111) at the interface.

Genetic basis and evolutionary mechanisms responsible for maintaining variation in broad personality traits remain the mysteries. Recently, Extraversion that is the most known broad personality tra...

Polymorphisms in genes of circadian system family seem to be of most importance for understanding of mechanisms underlying self-assessed individual variation in morning–evening preference. A review of earlier reported positive findings indicated that, at least, four polymorphisms in period circadian clock 3 (PER3) showed significant association with, at least, one of sub-constructs of a morningness–eveningness scale. However, similar to other candidate gene studies, these studies suffer from increased likelihood of false positive findings. We tried to replicate some of the most recently published positive results on associations of sub-traits of morningness–eveningness with two PER3 non-synonymous single nucleotide polymorphisms. DNA from buccal swabs was collected from healthy residents of three Russian cities, Moscow (N = 149) and Novosibirsk and Stavropol (N = 248). The tested hypotheses were formulated in accord with the earlier reported positive findings: the rare alleles might be linked to a...

Fused‐pentagons results in an increase of local steric strain according to the isolated pentagon rule (IPR), and for all reported non‐IPR clusterfullerenes multiple (two or three) metals are required to stabilize the strained fused‐pentagons, making it difficult to access the single‐atom properties. Herein, we report the syntheses and isolations of novel non‐IPR mononuclear clusterfullerenes MNC@C76 (M=Tb, Y), in which one pair of strained fused‐pentagon is stabilized by a mononuclear cluster. The molecular structures of MNC@C76 (M=Tb, Y) were determined unambiguously by single‐crystal X‐ray diffraction, featuring a non‐IPR C 2v(19138)‐C76 cage entrapping a nearly linear MNC cluster, which is remarkably different from the triangular MNC cluster within the reported analogous clusterfullerenes based on IPR‐obeying C82 cages. The TbNC@C76 molecule is found to be a field‐induced single‐molecule magnet (SMM).

The Dy-Sc nitride clusterfullerene Dy2ScN@C80-Ih exhibits slow relaxation of magnetization up to 76 K. Above 60 K, thermally-activated relaxation proceeds via the fifth-excited Kramers doublet with the energy of 1735 ± 21 K, which is the highest barrier ever reported for dinuclear lanthanide single molecule magnets.

By the combination of 9a-azaphenalene and a perpendicularly oriented acene, we have synthesized three derivatives of a series of novel, fully-conjugated nitrogen-containing polycyclic aromatic hydrocarbons (PAHs), namely [7,8]naphtho[2′,3′:1,2]indolizino[6,5,4,3-def]phenanthridine, with an acetylene triisopropylsilyl (TIPS), phenyl or benzothiophenyl substituent. Their optoelectronic properties were studied via UV-Vis-NIR absorption, fluorescence spectroscopy and cyclic voltammetry. In addition, in situ spectroelectrochemistry was performed to investigate the optical and magnetic properties of the mono-radical cation and anion by quasi-reversible oxidation and reduction of 11-(tert-butyl)-5,17-bis((triisopropylsilyl)ethynyl)[7,8]naphtho[2′,3′:1,2]indolizino[6,5,4,3-def]phenanthridine (1a). Theoretical modelling confirmed the predominately closed-shell electronic ground state with a weak diradical character depending on the geometry.

The combined W-band pulsed light-induced multiresonance ESR/ENDOR/TRIPLE technique and DFT calculation have been applied to study the 1H hyperfine coupling and electron spin density distribution on PPV cation and PC61BM anion radicals in (PPVs):PC61BM blends. The sign of calculated electron spin density populations of protons delocalized on polymer and fullerene side chain has been confirmed experimentally by means of TRIPLE in frozen solution at the temperature of 20 K.

Herein, we demonstrate an efficient synthesis of two antiaromatic constitutional isomers of pyrene-fused dicyclopenta[

The hunt for high-performance single-molecule magnets (SMM) revealed that atomic and molecular lanthanide systems combining 4f-shell and valence magnetism (FV-magnetism) may show magnetic bistability up to unexpectedly high temperatures. Here we rationalize the stability of the magnetism in the FV-systems from first principles on the example of LnII(CpiPr5)2 molecules.

Conspectus A characteristic phenomenon of lanthanide–fullerene interactions is the transfer of metal valence electrons to the carbon cage. With early lanthanides such as La, a complete transfer of six valence electrons takes place for the metal dimers encapsulated in the fullerene cage. However, the low energy of the σ-type Ln–Ln bonding orbital in the second half of the lanthanide row limits the Ln2 → fullerene transfer to only five electrons. One electron remains in the Ln–Ln bonding orbital, whereas the fullerene cage with a formal charge of −5 is left electron-deficient. Such Ln2@C80 molecules are unstable in the neutral form but can be stabilized by substitution of one carbon atom by nitrogen to give azafullerenes Ln2@C79N or by quenching the unpaired electron on the fullerene cage by reacting it with a chemical such as benzyl bromide, transforming one sp2 carbon into an sp3 carbon and yielding the monoadduct Ln2@C80(CH2Ph). Because of the presence of the Ln–Ln bonding molecular orbital with one electron, the Ln2@C79N and Ln2@C80(R) molecules feature a unique single-electron Ln–Ln bond and an unconventional +2.5 oxidation state of the lanthanides. In this Account, which brings together metallofullerenes, molecular magnets, and lanthanides in unconventional valence states, we review the progress in the studies of dimetallofullerenes with single-electron Ln–Ln bonds and highlight the consequences of the unpaired electron residing in the Ln–Ln bonding orbital for the magnetic interactions between Ln ions. Usually, Ln···Ln exchange coupling in polynuclear lanthanide compounds is weak because of the core nature of 4f electrons. However, when interactions between Ln centers are mediated by a radical bridge, stronger coupling may be achieved because of the diffuse nature of radical-based orbitals. Ultimately, when the role of a radical bridge is played by a single unpaired electron in the Ln–Ln bonding orbital, the strength of the exchange coupling is increased dramatically. Giant exchange coupling in endohedral Ln2 dimers is combined with a rather strong axial ligand field exerted on the lanthanide ions by the fullerene cage and the excess electron density localized between two Ln ions. As a result, Ln2@C79N and Ln2@C80(CH2Ph) compounds exhibit slow relaxation of magnetization and exceptionally high blocking temperatures for Ln = Dy and Tb. At low temperatures, the [Ln3+–e–Ln3+] fragment behaves as a single giant spin. Furthermore, the Ln–Ln bonding orbital in dimetallofullerenes is redox-active, which allows its population to be changed by electrochemical reactions, thus changing the magnetic properties because the change in the number of electrons residing in the Ln–Ln orbital affects the magnetic structure of the molecule.

We aim to find a non-invasive methodology to evaluate meat freshness and beginning of spoilage through visible and near-infrared spectroscopy. We have used two configurations capable to sense at different probing depths. A table-top spectrophotometer equipped with an integrating sphere was utilized for a shallow probing depth (80 μm) and covered 400-1700 nm spectral range. In another configuration, a fiber-optic linear array was coupled to a portable spectrophotometer (400-1000 nm) for increasing the average probing depth up to 570 μm. According to the results, it is possible to observe the decreasing trend in the light absorbance in both visible and NIR spectral ranges showing loss of freshness and meat spoilage over time. In the visible wavelength range, absorbance changes at 540 nm and 580 nm wavelengths allow for monitoring oxymyoglobin degradation, which is associated with loss of freshness. In the NIR region, monitoring changes in the absorbance of fat (1200 nm), water (1450 nm), and proteins (1525 and 1600 nm) show promise to detect spoilage. Specifically, absorbance of the superficially located oxymyoglobin decays immediately but only after 4 hours at the depth of 0.57 mm, while absorbance of surface water and protein components experiences a steep decrease only after about 2.5 hours that could be interpreted as a beginning of the spoilage process. The fiber-optic approach capable for real-time, non-destructive, inexpensive, and multi-component detection using a wide range of studied wavelengths is a great promise to design a compact, portable device for a variety of users at the meat supply chain.

A series of compounds with Sc

Murine Krebs-2 tumor-initiating stem cells are known to natively internalize extracellular double-stranded DNA fragments. Being internalized, these fragments interfere in the repair of chemically induced interstrand cross-links. In the current investigation, 756 bp polymerase chain reaction (PCR) product containing bulky photoreactive dC adduct was used as extracellular DNA. This adduct was shown to inhibit the cellular system of nucleotide excision repair while being resistant to excision by this DNA repair system. The basic parameters for this DNA probe internalization by the murine Krebs-2 tumor cells were characterized. Being incubated under regular conditions (60 min, 24°C, 500 μL of the incubation medium, in the dark), 0.35% ± 0.18% of the Krebs-2 ascites cells were shown to natively internalize modified DNA. The saturating amount of the modified DNA was detected to be 0.37 μg per 10

A solution, solid‐state, and computational study is reported of polycyclic aromatic hydrocarbon PAH/PAH(CF3)n donor/acceptor (D/A) charge‐transfer complexes that involve six PAH(CF3)n acceptors with known gas‐phase electron affinities that range from 2.11(2) to 2.805(15) eV and four PAH donors, including seven CT co‐crystal X‐ray structures that exhibit hexagonal arrays of mixed π‐stacks with 1/1, 1/2, or 2/1 D/A stoichiometries (PAH=anthracene, azulene, coronene, perylene, pyrene, triphenylene; n=5, 6). These are the first D/A CT complexes with PAH(CF3)n acceptors to be studied in detail. The nine D/A combinations were chosen to allow several structural and electronic comparisons to be made, providing new insights about controlling D/A interactions and the structures of CT co‐crystals. The comparisons include, among others, CT complexes of the same PAH(CF3)n acceptor with four PAH donors and CT complexes of the same donor with four PAH(CF3)n acceptors. All nine CT complexes exhibit charge‐transfer bands in solution with λ max between 467 and 600 nm. A plot of E(λ max) versus [IE(donor)−EA(acceptor)] for the nine CT complexes studied is linear with a slope of 0.72±0.03 eV eV−1. This plot is the first of its kind for CT complexes with structurally related donors and acceptors for which precise experimental gas‐phase IEs and EAs are known. It demonstrates that conclusions based on the common assumption that the slope of a CT E(λ max) versus [IE−EA] plot is unity may be incorrect in at least some cases and should be reconsidered., Accept the charge: Comprehensive solution/solid‐state/computational study of polycyclic aromatic hydrocarbon PAH/PAH(CF3)n donor/acceptor charge‐transfer complexes involving PAH(CF3)n acceptors with electron affinities from 2.11 to 2.85 eV and four PAH donors with ionization energies from 6.96 to 7.44 eV, including seven X‐ray crystal structures exhibiting hexagonal arrays of mixed π‐stacks with 1/1, 1/2, or 2/1 D/A stoichiometries.

A comparative analysis of the energy characteristics of the basic structural schemes of integrated voltage regulators is carried out, taking into account losses in the control circuits. It is shown that the introduction of the dependences of the inherent current consumption on the load current significantly improves the energy parameters of the integrated voltage regulators within the range of small and medium values of the load current. The original circuitry of the proposed integrated voltage regulators with an adaptive static mode is considered, their work is analyzed. Voltage regulators of the considered subclass are designed to serve precision analog circuits (active RC-filters, operational amplifiers, analog-to-digital converter, etc).

The azafullerene Tb-2@C79N is found to be a single-molecule magnet with a high 100-s blocking temperature of magnetization of 24 K and large coercivity. Tb magnetic moments with an easy-axis single-ion magnetic anisotropy are strongly coupled by the unpaired spin of the single-electron Tb-Tb bond. Relaxation of magnetization in Tb-2@C79N below 15 K proceeds via quantum tunneling of magnetization with the characteristic time tau(QTM)=16462 +/- 1230 s. At higher temperature, relaxation follows the Orbach mechanism with a barrier of 757 +/- 4 K, corresponding to the excited states, in which one of the Tb spins is flipped. European Union's Horizon 2020 research and innovation programme, European Research Council [648295]; European Union's Horizon 2020 research and innovation programme, Marie Sklodowska-Curie action [748635]; Deutsche Forschungsgemeinschaft [PO 1602/4-1, 1602/5-1]; Luther & Alice Hamlett Scholarship We acknowledge funding from the European Union's Horizon 2020 research and innovation programme, European Research Council (grant agreement No 648295 to A.A.P.), and Marie Sklodowska-Curie action (grant agreement No. 748635 to S.M.A.), and the Deutsche Forschungsgemeinschaft (grants PO 1602/4-1 and 1602/5-1 to A.A.P.). K.K. acknowledges financial support from a Luther & Alice Hamlett Scholarship. Computational resources were provided by the Center for High Performance Computing at the TU Dresden. We appreciate the help from Dr. Anja U. B. Wolter and Sebastian Gass in magnetic measurements and technical support with computational resources in IFW Dresden by Ulrike Nitzsche.

Endohedral fullerenes, such as Dy2ScN@C80, are single-molecule magnets with long relaxation times of their magnetization. An open and anisotropic 4f electron shell in the lanthanides (here Dy) imposes a magnetic moment that maintains its orientation at liquid-helium temperatures for macroscopic times. If these molecules shall be used as single-bit information storage elements or for quantum operations, the orientation of the endohedral units and the orientation of the magnetic moments has to be controlled. X-ray absorption spectroscopy (XAS) and magnetic circular dichroism (XMCD)—with variation of the angle of x-ray incidence—allows for the detection of these two structural elements. We present XMCD data of Dy2ScN@C80 on an h−BN/Rh(111) nanomesh that display at 2 K a large hysteresis with a coercive field of 0.4 T. The angular dependence of the XAS data at the Dy M5 edge indicates partial ordering of the endohedral units. In order to quantify anisotropic orientation we introduce the “deviation” D as an operational quantity that measures differences between two spectra.

The statistical indicators of the dynamic properties of chaotic systems approximated in discrete phase spaces of final states are investigated. It is shown that the studied systems have finite orbits and fixed points. Algorithms for finding and constructing orbits of a finite period and fixed points are proposed.

Polycyclic aromatic azomethine ylides (PAMYs) are versatile building blocks for the bottom-up construction of unprecedented nitrogen-containing polycyclic aromatic hydrocarbons (N-PAHs). Here, we demonstrate the 1,3-dipolar cycloaddition between PAMY and 1,4-diphenylbut-2-yne-1,4-dione and the subsequent condensation reaction with hydrazine, which led to unique N-PAHs with a phenyl-substituted pyrrolopyridazine core (PP-1 and PP-2). The molecular structures of pristine PP-1 and tert-butyl-substituted PP-2 were verified by NMR spectroscopy and mass spectrometry. Moreover, the structure of PP-2 was unambiguously elucidated by X-ray single crystal analysis. The optoelectronic properties were investigated by solvent-dependent UV-Vis absorption and fluorescence emission spectroscopy as well as cyclic voltammetry. Additionally, density functional theory (DFT) calculations showed that PP-1 and PP-2 exhibit push-pull behavior. Furthermore, in situ EPR/UV-Vis-NIR spectroelectrochemistry allowed the detailed insight into the spectroscopic properties and spin distribution of radical cation species of PP-2.

Two novel nonhexagonal ring fused NBN-dibenzophenalenes (NBN-penta and NBN-hepta) were designed and synthesized. X-ray analysis reveals the planar structure of NBN-penta, while NBN-hepta displays a double-helical structure. Both compounds possess higher oxidation potential compared to the NBN-type zigzag-edged polycyclic aromatic hydrocarbons. The resultant NBN-penta and NBN-hepta exhibit global aromatic character based on X-ray analysis and DFT calculations. Furthermore, single crystal transistors of NBN-penta and NBN-hepta were fabricated, manifesting their promising potential in organic electronics.

This work includes a study based on software simulation of impulse neuron behavior using Izhikevich neuron model, synaptic plasticity and additional tools for their cooperation. Additional examples demonstrating different effects of impulse neural network behavior were also developed during the study of these effects. Software model was compared to biological behavior and mathematical model, and application of complex neural models to object-oriented programming was studied.