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Abstract: The nature of the superconducting state of the yttrium high-temperature superconductor is discussed, and the causes and mechanism of superconductivity are considered. A perovskite structure is used as an example to calculate the bond length and the lengths of elastic and electron waves. The Fermi energy and the charge density sphere radius are calculated. The first ionization potential of copper is, in essence, the kinetic energy of an elastic longitudinal wave. A hypothesis is advanced to explain the origin of superconductivity in this superconductor. [ABSTRACT FROM AUTHOR]

Ultraviolet photoelectron spectroscopy (UPS) and cyclic voltammetry (CV) are employed to measure energy levels for charge transport in organic semiconductor films. A series of classical molecules/polymers used in organic bulk heterojunction solar cells are deposited on platinum substrates/electrodes to form thin films and a linear relationship of vertical ionization potential (IP) measured by UPS and relative oxidation potential (Eox) obtained by CV is found, with a slope equal to unity. The intercept varies with the different reference redox couples and repeated potential sweep numbers during experiment processes. The relationship provides for an easy conversion of values obtained by the two techniques and correlates well with device parameters. The precision in the CV‐derived IP values is not sufficient, however, to enable precise design of energy level alignment at heterojunction and the approach does not improve upon the current “best practice” for obtaining donor ionization potential–acceptor electron affinity gaps at heterojunctions. [ABSTRACT FROM AUTHOR]

Two electroactive compounds, bearing 2,3-dimethylindole donor moiety and tetrafluorostyrene acceptor moiety, were designed and synthesized by employing one-step nucleophilic aromatic substitution reaction. Radical polymerization was used to obain electroactive linear polymer. Their photophysical properties, based on theoretical calculations and experimental measurements, as well as electrochemical and photoelectrical properties are discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this article, we investigate the performance of different approximate variants of the EOM‐CCSD method for calculation of ionization potential (IP), as compared to EOM‐CCSDT reference values. None of the lower scaling approximations to the EOM‐CCSD method give a consistent performance for valence, inner valence, and core ionization, favoring one, or the other depending on the nature of the approximation used. The parent EOMIP‐CCSD method gives superior performance for valence IP but can show large errors for inner valence and core ionization. The problem is particularly severe for core‐ionization, where even the EOMIP‐CCSDT method cannot provide quantitative accuracy. [ABSTRACT FROM AUTHOR]

Low-cost bicarbazole-based hole transporting derivative with diphenylvinyl substitutions was synthesized by simple procedure and characterized. The respective glass transition temperature of the material was estimated to be 81 °C, which can provide morphologically-stable amorphous films for applications in organic light emitting diodes. The compound possesses an adequate ionization potential, suitable triplet energy and high hole drift mobility of 5.54 eV, 2,61 eV and of 2 × 10 −3  cm 2 /V·s, respectively, which make it a suitable hole transporting material for use in red phosphorescent organic light-emitting diodes. The respective peak efficiency of the red device with the p-type dopant was recorded at 8.3% (5.2 cd/A and 3.3 lm/W) and at 7.8% (4.9 cd/A and 1.9 lm/W) for 100 cd/m [2] brightness, demonstrating high potential of the material for applications in light emitting diodes. The characteristics indicated that device with the bicarbazole-based compound exhibited better performance than those of widely used 1,1-bis [(di-4-tolylamino)phenyl]cyclohexane (TAPC) -based device. [ABSTRACT FROM AUTHOR]

Supramolecular, molecular and electronic structures of petroleum resins are studied. The experimental part includes isolation of resins by the eluent method and measuring electron and IR spectra. The structural parameters are calculated by molecular mechanics and DFT/B3LYP methods. The calculated data are in good agreement with the experiment. The nonplanar structure of petroleum resins is confirmed by the results of our structural study. [ABSTRACT FROM AUTHOR]

The electronic properties, such as binding energy, magnetic property, charge transfer, ionization potential, and electron affinity, of Nin-1Al (n = 2-20) neutral and ionic clusters are studied using the density functional theory calculations with the PBE exchange-correlation energy functional. The calculated total magnetic moments and ionization potential can decrease and increase with the addition of the Al atom, respectively. The calculated electron affinity has occurred with no significant change, except the Ni16Al cluster. [ABSTRACT FROM AUTHOR]

Phosphorene nanoflakes of different shapes and sizes were studied at the hybrid BHandHLYP level of theory. This functional accurately reproduces the experimental bond lengths and valence angles of black phosphorus. All nanoflakes were found to have a singlet ground state and their band gaps (E g s) decrease linearly with 1/N, where N is the number of P atoms in the nanoflakes. It seems that the topology of the nanoflake edges does not affect E g . The ionization potentials (IPs) and electron affinities (EAs) generally grow smaller with increasing nanoflake size. The change in IPs and EAs with size correlate with the delocalization pattern of polaron cations and anions. The shape and nature or the longest edge (zig-zag or armchair) affect both the IP and EA. Nanoflakes with a long zigzag edge have higher IPs and lower EAs compared to square systems. Low theoretically calculated hole reorganization energies (less than 0.1 eV) are in agreement with the experimentally determined high hole mobility in phosphorene. The low hole reorganization energies are due to the better ability of phosphorene nanoflakes to delocalize polaron cations compared to polaron anions. [ABSTRACT FROM AUTHOR]

Purpose Polymeric drugs, including patiromer (Veltassa®), bind target molecules or ions in the gut, allowing fecal elimination. Non-absorbed insoluble polymers, like patiromer, avoid common systemic drug-drug interactions (DDIs). However, the potential for DDI via polymer binding to orally administered drugs during transit of the gastrointestinal tract remains. Here we elucidate the properties correlated with drug-patiromer binding using quantitative structure-property relationship (QSPR) models. Methods We selected 28 drugs to evaluate for binding to patiromer in vitro over a range of pH and ionic conditions intended to mimic the gut environment. Using this in vitro data, we developed QSPR models using step-wise linear regression and analyzed over 100 physiochemical drug descriptors. Results Four descriptors emerged that account for ~70% of patiromer-drug binding in vitro: the computed surface area of hydrogen bond accepting atoms, ionization potential, electron affinity, and lipophilicity (R 2  = 0.7, Q 2  = 0.6). Further, certain molecular properties are shared by nonbinding, weak, or strong binding compounds. Conclusions These findings offer insight into drivers of in vitro binding to patiromer and describe a useful approach for assessing potential drug-binding risk of investigational polymeric drugs. [ABSTRACT FROM AUTHOR]

Nowadays considerable attention has been given for researches on magnetic properties of transition metal clusters (specifically F e N and C o N ). This is because these clusters offer big hopes for the possibility of presenting significant magnetic anisotropy energy which is critical for technological applications. This study intends to find out the causes for the existence of the two states (ground and meta-stable) in Iron and Cobalt clusters. The study also explains the role of valence electrons for the existence of magnetism in the two states by using the concept of ionization potential, electron dipole polarizabilities, chemical hardness and softness of the clusters. Assuming that, when all itinerant electrons are at s-level and also at the d-level ( n s = n a n d n s → 0. ) the ground state and meta-stable state energies with distinct energy minima are ( E g s = l / 2 n + ε c n − 2 μ B h n a n d E m s = ε d n − g μ B h n ) respectively. The findings also showed that polarizability of small cluster of the specified elements are increased compared with the bulk value, which means that there is an effective increase in the cluster radius due to the spilling out of the electronic charge. Furthermore, it is obvious that 4s electrons are more delocalized than the 3d electrons so that they spill out more than the 3d electrons. This leads to the conclusion that 4s electrons are primarily responsible for the enhanced polarizabilities and for shell structure effects. This indicates that polarizability at the meta-stable state is less than that of the ground state i.e. the meta-stable state loses its s electron. Therefore the two minima represent a ground state of configuration 3 d ↑ 5 3 d ↓ 2 + δ 4 s 2 − δ with energy E g s and meta-stable state of configuration 3 d ↑ 5 3 d ↓ 3 + δ 4 s 1 − δ with energy E m s for Co clusters and a ground state configuration 3 d ↑ 5 3 d ↓ 1 + δ 4 s 2 − δ with energy E g s an meta-stable state of configuration 3 d ↑ 5 3 d ↓ 2 + δ 4 s 1 − δ with energy E m s for Fe clusters. Hence, the existence of the two states (meta-stable & ground state) is due to the large disproportion in electronic configurations of the two clusters at their respective states. Furthermore, the chemical hardness and softness of the clusters also provide evidence for the existence of stability of the two states depending on the cluster size. [ABSTRACT FROM AUTHOR]

Two polyethers containing electroactive pendent 4-(carbazol-2-yl)-7-arylbenzo[c]-1,2,5-thiadiazole moieties have been synthesized by the multi-step synthetic route. Full characterization of their structures is presented. The polymers represent derivatives of very high thermal stability with initial thermal degradation temperatures of 425 °C and 431 °C. Glass transition temperatures of the amorphous materials were also very high and reached values of 154 °C and 163 °C. The electron photoemission spectra of thin layers of the polymers showed ionization potentials of 5.84 eV and 5.93 eV. Hole-transporting properties of the polymeric materials were tested in the structures of organic light emitting diodes with Alq 3 as the green emitter and electron transporting material. An electroluminescent device containing hole-transporting layer (HTL) of the polymer with electroactive 4-carbazolyl-7-phenylbenzo[c]-1,2,5-thiadiazole moieties exhibited turn on voltage of 6.2 V, maximum photometric efficiency of 2.5 cd/A and maximum brightness exceeding 300 cd/m 2 . The device containing HTL of the polymer with 4-carbazolyl-7-(1-naphtyl)benzo[c]-1,2,5-thiadiazole moieties demonstrated turn on voltage of 5.2 V, maximum photometric efficiency of 1.6 cd/A and maximum brightness exceeding 1500 cd/m 2 . The efficiencies were about 30–90% higher than that of the device containing widely used hole transporting layers of poly(9-vinylcarbazole). [ABSTRACT FROM AUTHOR]

The lowest electronic states of boron monoiodide, BI, and its ions BI ± have been theoretically studied by the multireference configuration interaction technique employing basis sets of quadruple and quintuple-ζ quality. Scalar relativistic effects and spin-orbit coupling are taken into account as well. For all states we report potential energy curves, binding energies, and spectroscopic constants. Some quantities such as electron affinity, ionization potential, and dipole moment of BI are evaluated for the first time. The nature of the bonding in the systems under scrutiny is also discussed in some detail. [ABSTRACT FROM AUTHOR]

The new experimental results on the effective quantum numbers and term energies of the highly excited odd-parity 4s4d3D1,2,3→4snf3F2,3,4Rydberg transitions of zinc have been presented. The experiment was performed using the three dye lasers simultaneously pumped by the second harmonic (532 nm) of the Q-switched Nd:YAG laser. The new observation includes the 4snf3F3(12 ≤n ≤ 50) series excited from the 4s4d3D2intermediate level. In addition, the 4snf3F2(12 ≤n ≤ 28) and 4snf3F4(12 ≤n ≤ 33) series are observed from the thermally populated 4s4d3D1,3fine structure components. The ionization potential of zinc has been determined from the unperturbed 4snf3F3series as 75769.31 ± 0.15 cm−1, which is in excellent agreement with the previously reported value. [ABSTRACT FROM PUBLISHER]

Phenylethenyl substituted 10-alkylphenoxazines were synthesized by a multi-step synthetic route. The derivatives were characterized by thermo-gravimetric analysis, differential scanning calorimetry, electron photoemission and time of flight technique. The materials were found to show very high thermal stability having initial thermal degradation temperatures in the range of 338–354 °C. Glass transition temperatures of the low molar mass materials were in the rage of 41–49 °C. The electron photoemission spectra of thin layers of the derivatives showed ionization potentials in the range of 5.16–5.3 eV. Hole drift mobility in thin layers of these derivatives ranged from 6 × 10 −4 cm 2 V −1 s −1 to 4.5 × 10 −3 cm 2 V −1 s −1 at high electric fields at room temperature. The synthesized materials have been tested as hole transporting layers in electroluminescent bilayer organic light emitting diodes with tris(quinolin-8-olato)aluminium as an emitter. The device with hole transporting layer comprised of 3,7-di(2-phenylethenyl)-10-(2-ethylhexyl)phenoxazine exhibited the best overall performance with low turn-on voltage of 2.8 V, a maximum photometric efficiency of about 3 cd/A and maximum brightness of 2160 cd/m 2 . Taking the device at 1000 cd/m 2 , the photometric efficiency was increased by 25%, as compared with that of PEDOT:PSS-based device. [ABSTRACT FROM AUTHOR]

Herein, we present a flow-through electro-Fenton system for highly efficient and selective degradation of organic contaminants. The essential to this design was a functional nanohybrid filter cathode consisting of an electroactive carbon nanotubes (CNT) filter functionalized with bimetallic Fe/Mn oxide nanoparticles under nanoconfinement. Results suggested that the nanoconfined Fe/Mn-in-CNT filter exhibited a much higher organic degradation kinetics (1.65 times) relative to its unconfinement counterpart (Fe/Mn-out-CNT). Singlet oxygen was the primary reactive oxygen species in the Fe/Mn-in-CNT-based system, in sharp contrast with the hydroxyl radical-mediated pathway in the Fe/Mn-out-CNT-based system. The efficacy was closely correlated with the ionization potential of target organic molecules, with preferentially oxidized organics with the electron-donating ability. Both experimental evidences and theoretical results collectively revealed the superior performance associated with the synergistic effects among Fe, Mn, CNT, and electric field in the nanoconfined system. [Display omitted] • A nanoconfined flow-through electro-Fenton system was developed for organic decontamination. • The nanoconfined system outperformed unconfined system in BPA degradation kinetics. • 1O 2 dominated the degradation of BPA in the Fe/Mn-in-CNT-based system. • An IP-dependent micropollutants degradation mechanism was identified. • DFT calculations elucidated the superior performance of the nanoconfined system. [ABSTRACT FROM AUTHOR]