Unveiling Charge Carrier Dynamics at Organic-Inorganic S-Scheme Heterojunction Interfaces: Insights From Advanced EPR.

Understanding charge carrier transfer at heterojunction interfaces is critical for advancing solar energy conversion technologies. This study utilizes continuous wave (CW), pulse, and time-resolved (TR) electron paramagnetic resonance (EPR) spectroscopy to explore the radical species formed at the TAPA (tris(4-aminophenyl)amine)-PDA (Terephthaldicarboxaldehyde)/ZnInS (TP/ZIS) heterojunction interface. CW and pulse EPR identify stable radical defects localized near the interface, accessible to water molecules.

Relationship of Iron Deficiency, Anemia and Combination of Iron Deficiency With Anemia With Severity of Manifestations of Chronic Heart Failure. Additional Analysis of the Study "Prevalence of Iron Deficiency in Patients With Chronic Heart Failure in the Russian Federation (J-CHF-RF)".

Aim      To evaluate the role of iron deficiency (ID) identified by various criteria, anemia, and the combination of ID and anemia in determining the severity of the clinical course of chronic heart failure (CHF) in a retrospective analysis of data from 498 patients who participated in the ID-CHF-RF Russian multicenter program.Material and methods  ID was diagnosed by the following three criteria established by the European Society of Cardiology (ESC) and the Russian Society of Cardiology (RSC): 1) ferritin concentration <100 μg/l or ferritin concentration 100-299 μg/l in combination with a decreased transferrin saturation (TS) <20%; 2) ID criteria that showed a high sensitivity and specificity when compared with bone marrow morphology (BMM): TS ≤19.8% or serum iron (SI) ≤13 μmol/l; and 3) a composite index including a ferritin concentration <100 μg/l in combination with TS <20% and SI ≤13 μmol/l.

Investigation of slow magnetic relaxation in a series of 1D polymeric cyclobutane-1,1-dicarboxylates based on LnVIV2 units (Ln = Tb, Dy, Ho, Er, Tm, Yb): rare examples of V-4f single-molecule magnets.

The reactions of VOSO·3HO with Na(cbdc) (cbdc - dianion of cyclobutane-1,1-dicarboxylic acid) and lanthanide(III) nitrates taken in a molar ratio of 1 : 2 : 1 were found to yield a series of isostructural heterometallic compounds [NaLn(VO)(cbdc)(HO)] (1Ln, Ln = Tb, Dy, Ho, Er, Tm, Yb). These compounds are constructed from trinuclear anionic units [Ln(VO)(cbdc)(HO)] ({LnV}) linked by Na ions into 1D polymeric chains. The crystal structures of 1Dy and 1Er were determined by single-crystal X-ray diffraction (XRD), and their isostructurality with 1Tb, 1Ho, 1Tm, and 1Yb was proved by powder X-ray diffraction (PXRD).

Origin of Intersystem Crossing in Red-Light Absorbing Bodipy Derivatives: Time-Resolved Transient Optical and Electron Paramagnetic Resonance Spectral Studies with Twisted and Planar Compounds.

We studied the intersystem crossing (ISC) property of red-light absorbing heavy atom-free dihydronaphtho[]-fused Bodipy derivatives (with phenyl group attached at the lower rim via ethylene bridge, taking constrained geometry, i.e., and the half-oxidized product ) and dispiroflourene[]-fused Bodipy () that have a twisted π-conjugated framework.

Temperature Dependence of the Sensitivity of PVDF Pyroelectric Sensors to THz Radiation: Towards Cryogenic Applications.

The application of terahertz (THz) science in industrial technology and scientific research requires efficient THz detectors. Such detectors should be able to operate under various external conditions and conform to existing geometric constraints in the required application. Pyroelectric THz detectors are among the best candidates.

Xerogel mesoporous materials based on ultrastable Blatter radicals for efficient sorption of nitric oxide.

The reduction of hazardous nitric oxide emissions remains a significant ecological challenge. Despite the variety of possibilities, sorbents able to capture low concentrations of NO from flue gas with high selectivity are still in demand. In this work a new type of mesoporous xerogel material highly loaded with ultrastable Blatter radicals (BTR, >60 % by mass) that act as selective NO sorption sites is developed.

[Relationship between cognitive status and other geriatric syndromes in patients aged 65 years and older with chronic heart failure.].

This article presents the incidence of geriatric syndromes in patients with chronic heart failure 65 years of age and older, depending on cognitive status. At the Russian gerontological center, 149 people with confirmed chronic heart failure were selected according to the European criteria of 2021. In this sample, 50,3% of patients had mild cognitive impairment, and 17,5% had severe cognitive impairment.

Calculation of π Using a Molecular Electron Spin Qubit Implemented by Pulsed Electron Paramagnetic Resonance.

The present letter demonstrates a simple method to characterize the molecular electron spin qubits, for which a large number of chemical compounds with non-zero spin have been proposed. The method is based on calculating the value of π using a one-qubit protocol based on obtaining and processing Rabi oscillations. It was implemented using a model system of a Finland trityl radical with an electron spin = 1/2 and a pulsed electron paramagnetic resonance spectrometer.

Charge Transfer and Intersystem Crossing in Compact Naphthalenediimide-Phenothiazine Triads: Synthesis and Study of the Photophysical Property with Transient Optical and Electron Paramagnetic Resonance Spectroscopic Methods.

In order to obtain a long-lived charge separation (CS) state in compact electron donor-acceptor molecular systems, we prepared a series of naphthalenediimide (NDI)-phenothiazine (PTZ) triads, with phenylene as the linker between the donor and acceptor. Conformation restriction is imposed to control the mutual orientation of the NDI and PTZ units by attaching methyl groups on the phenylene linker to tune the electronic coupling between the donor and the acceptor. Moreover, the PTZ moiety was oxidized to sulfoxide to tune the ordering of the CS state and the LE state (LE: locally excited state).

Inductive detection of temperature-induced magnetization dynamics of molecular spin systems.

The development and technological applications of molecular spin systems require versatile experimental techniques to characterize and control their static and dynamic magnetic properties. In the latter case, bulk spectroscopic and magnetometric techniques, such as AC magnetometry and pulsed electron paramagnetic resonance, are usually employed, showing high sensitivity, wide dynamic range, and flexibility. They are based on creating a nonequilibrium state either by changing the magnetic field or by applying resonant microwave radiation.

Toward New Horizons in Verdazyl-Nitroxide High-Spin Systems: Thermally Robust Tetraradical with Quintet Ground State.

High-spin organic tetraradicals with significant intramolecular exchange interactions have high potential for advanced technological applications and fundamental research, but examples reported to date exhibit limited stability and processability. In this work, we designed the first tetraradical based on an oxoverdazyl core and nitronyl nitroxide radicals and successfully synthesized it using a palladium-catalyzed cross-coupling reaction of an oxoverdazyl radical bearing three iodo-phenylene moieties with a gold(I) nitronyl nitroxide-2-ide complex in the presence of a recently developed efficient catalytic system. The molecular and crystal structures of the tetraradical were confirmed by single crystal X-ray diffraction analysis.

Nanoscale solvent organization in metal-organic framework ZIF-8 probed by EPR of flexible β-phosphorylated nitroxides.

Metal-organic frameworks (MOFs) draw increasing attention as nanoenvironments for chemical reactions, especially in the field of catalysis. Knowing the specifics of MOF cavities is decisive in many of these cases; yet, obtaining them remains very challenging. We report the first direct assessment of the apparent polarity and solvent organization inside MOF cavities using a dedicated structurally flexible spin probe.

Synthesis and photoinduced behavior of DPP-anchored nitronyl nitroxides: a multifaceted approach.

Understanding and controlling spin dynamics in organic dyes is of significant scientific and technological interest. The investigation of 2,5-dihydropyrrolo[4,3-]pyrrolo-1,4-dione derivatives (DPPs), one of the most widely used dyes in many fields, has so far been limited to closed-shell molecules. We present a comprehensive joint experimental and computational study of DPP derivatives covalently linked to two nitronyl nitroxide radicals (DPP-NN).

Catalytic System for Cross-Coupling of Heteroaryl Iodides with a Nitronyl Nitroxide Gold Derivative at Room Temperature.

A simple and highly effective methodology for the cross-coupling of heteroaryl iodides with NN-AuPPh at room temperature is reported. The protocol is based on a novel catalytic system consisting of Pd(dba)·CHCl and the phosphine ligand CgPPh having an adamantane-like framework. The present protocol was found to be well compatible with various heteroaryl iodides, thus opening new horizons in directed synthesis of functionalized nitronyl nitroxides and high-spin molecules.

A Nitronyl Nitroxide-Substituted Benzotriazinyl Tetraradical.

High-spin organic tetraradicals with significant intramolecular exchange interactions have high potential for advanced technological applications and fundamental research, but those synthesized to date possess limited stability and processability. In this work, we have designed a tetraradical based on the Blatter's radical and nitronyl nitroxide radical moieties and successfully synthesized it by using the palladium-catalyzed cross-coupling reaction of a triiodo-derivative of the 1,2,4-benzotriazinyl radical with gold(I) nitronyl nitroxide-2-ide complex in the presence of a newly developed efficient catalytic system. The molecular and crystal structure of the tetraradical was confirmed by X-ray diffraction analysis.

Comparative Study of Single Crystal and Polymeric Pyroelectric Detectors in the 0.9-2.0 THz Range Using Monochromatic Laser Radiation of the NovoFEL.

The development of efficient and reliable sensors operating at room temperature is essential to advance the application of terahertz (THz) science and technology. Pyroelectric THz detectors are among the best candidates, taking into account their variety, outstanding performance, ease of fabrication, and robustness. In this work, we compare the performance of six different detectors, based on either LaTiO crystal or different polymeric films, using monochromatic radiation of the Novosibirsk Free Electron Laser facility (NovoFEL) in the frequency range of 0.

Female and Male Phenotypes of Iron Deficiency in CHF. Additional analysis of the «The Prevalence of Iron Deficiency in Patients With Chronic Heart Failure in the Russian Federation (J-CHF-RF)» study.

Aim    To evaluate the incidence of iron deficiency (ID) in men and women with chronic heart failure (CHF) and to compare clinical and functional indexes in patient with and without ID depending on the gender.Material and methods    An additional analysis of the study "Prevalence of Iron Deficiency in Patients With Chronic Heart Failure in the Russian Federation (ID-CHF-RF)" was performed. The study included 498 (198 women, 300 men) patients with CHF, in whom, in addition to iron metabolism, the quality of life and exercise tolerance (ET) were studied.

Revealing light-induced structural shifts in G-quadruplex-porphyrin complexes: a pulsed dipolar EPR study.

The binding of G-quadruplex structures (G4s) with photosensitizers is of considerable importance in medicinal chemistry and drug discovery due to their promising potential in photodynamic therapy applications. G4s can experience structural changes as a result of ligand interactions and light exposure. Understanding these modifications is essential to uncover the fundamental biological roles of the complexes and optimize their therapeutic potential.

Effects of Zwitterions on Structural Anomalies in Ionic Liquid Glasses Studied by EPR.

Ionic liquids (ILs) form a variety of nanostructures due to their amphiphilic nature. Recently, unusual structural phenomena have been found in glassy ILs near their glass transition temperatures; however, in all studied cases, IL cations and anions were in the form of separate moieties. In this work, we investigate for the first time such structural anomalies in zwitterionic IL glasses (ZILs), where the cation and anion are bound in a single molecule.

Efficient Spin-Orbit Charge-Transfer Intersystem Crossing and Slow Intramolecular Triplet-Triplet Energy Transfer in Bodipy-Perylenebisimide Compact Dyads and Triads.

Bodipy (BDP)-perylenebisimide (PBI) donor-acceptor dyads/triad were prepared to study the spin-orbit charge-transfer intersystem crossing (SOCT-ISC). For BDP-PBI-3, in which BDP was attached at the imide position of PBI, higher singlet oxygen quantum yield (Φ =85 %) was observed than the bay-substituted derivative BDP-PBI-1 (Φ =30 %). Femtosecond transient absorption spectra indicate slow Förster resonance energy transfer (FRET; 40.

High-field EPR of copper(II)-nitroxide compound exhibiting three-step phase transition: structural insights from the field-induced sample orientation.

Copper(II)-nitroxide based Cu(hfac)L compounds exhibit unusual magnetic behavior that can be induced by various stimuli. In many aspects, the magnetic phenomena observed in Cu(hfac)L are similar to classical spin-crossover behavior. However, these phenomena originate from polynuclear exchange-coupled spin clusters Cu-O˙-N< or >N-˙O-Cu-O˙-N<.

UiO-66 framework with an encapsulated spin probe: synthesis and exceptional sensitivity to mechanical pressure.

Probes sensitive to mechanical stress are in demand for the analysis of pressure distribution in materials, and the design of pressure sensors based on metal-organic frameworks (MOFs) is highly promising due to their structural tunability. We report a new pressure-sensing material, which is based on the UiO-66 framework with trace amounts of a spin probe (0.03 wt%) encapsulated in cavities.

Sensitivity optimization in pulse EPR experiments with photo-labels by multiple-echo-integrated dynamical decoupling.

Photo-excited triplet states represent a new class of spin labels in pulse electron paramagnetic resonance (EPR), attracting increasing attention because of their unique spectroscopic properties. Despite certain advantages, the use of photo-labels has also some challenges, low repetition rates due to technical laser-related limitations and intrinsic properties of the labels. The application of additional pulse trains for multiple refocusing of the electron spin echo and integration of all observed echoes can significantly enhance sensitivity at a given repetition rate.