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The effects of adsorption of Zn-phthalocyanine (ZnPc) molecules on the superconductivity of the Si(111)-(root7xroot3)-In surface are studied through transport measurements under ultrahigh vacuum environment. The ZnPc molecules are found to increase the transition temperature Tc by 11% at maximum, which is about 2.7 times the Tc increase previously reported using CuPc. By contrast, angle-resolved photoemission spectroscopy measurements and ab initio calculations show that charge transfer from the In atomic layers to ZnPc is substantially smaller than that to CuPc. This clearly shows that charge transfer should be excluded as the origin of the increase in Tc. The push-back effect induced by physical adsorption of molecules is discussed as a possible mechanism for the Tc enhancement.

Muscarinic M3 (M3) receptors mediate a wide range of acetylcholine (ACh)-induced functions, including visceral smooth-muscle contraction and glandular secretion. Positive allosteric modulators (PAMs) can avoid various side effects of muscarinic agonists with their spatiotemporal receptor activation control and potentially better subtype selectivity. However, the mechanism of allosteric modulation of M3 receptors is not fully understood, presumably because of the lack of a potent and selective PAM. In this study, we investigated the pharmacological profile of ASP8302, a novel PAM of M3 receptors, and explored the principal site of amino-acid sequences in the human M3 receptor required for the potentiation of receptor activation. In cells expressing human M3 and M5 receptors, ASP8302 shifted the concentration-response curve (CRC) for carbachol to the lower concentrations with no significant effects on other subtypes. In a binding study with M3 receptor–expressing membrane, ASP8302 also shifted the CRC for ACh without affecting the binding of orthosteric agonists. Similar shifts in the CRC of contractions by multiple stimulants were also confirmed in isolated human bladder strips. Mutagenesis analysis indicated no interaction between ASP8302 and previously reported allosteric sites; however, it identified threonine 230 as the amino acid essential for the PAM effect of ASP8302. These results demonstrate that ASP8302 enhances the activation of human M3 receptors by interacting with a single amino acid distinct from the reported allosteric sites. Our findings suggest not only a novel allosteric site of M3 receptors but also the potential application of ASP8302 to diseases caused by insufficient M3 receptor activation. SIGNIFICANCE STATEMENT The significance of this study is that the novel M3 receptor positive allosteric modulator ASP8302 enhances the activation of human M3 receptor by interacting with a residue distinct from the reported allosteric sites. The finding of Thr230 as a novel amino acid involved in the allosteric modulation of M3 receptors provides significant insight into further research of the mechanism of allosteric modulation of M3 and other muscarinic receptors.

Spatially controlling the Fermi level of topological insulators and keeping their electronic states stable are indispensable processes to put this material into practical use for semiconductor spintronics devices. So far, however, such a method has not been established yet. Here we show a novel method for doping a hole into n-type topological insulators Bi2X3 (X= Se, Te) that overcomes the shortcomings of the previous reported methods. The key of this doping is to adsorb H2O on Bi2X3 decorated with a small amount of carbon, and its trigger is the irradiation of a photon with sufficient energy to excite the core electrons of the outermost layer atoms. This method allows controlling the doping amount by the irradiation time and acts as photolithography. Such a tunable doping makes it possible to design the electronic states at the nanometer scale and, thus, paves a promising avenue toward the realization of novel spintronics devices based on topological insulators.

Muscarinic MModulation of carbachol-induced increases in intracellular CaASP8302 demonstrated PAM effects on the rat MOur results in rats indicate that ASP8302 improves voiding dysfunction by potentiating bladder contraction with fewer effects on cholinergic responses in other organs, and suggest a potential advantage over current cholinomimetic drugs for treating micturition disorders caused by insufficient bladder contraction.

Muscarinic M

In this review, we summarize the recent progress in the understanding of the spin-polarized electronic states in two-dimensional (2D) atomic layer materials (ALMs) formed on solid surfaces. The spin-polarized electronic states caused by the combination of spin-orbit coupling (SOC) with broken spatial inversion symmetry along the surface normal direction is one of the most exotic phenomena that appears on ALMs formed on solid surfaces as well as clean solid surfaces. The so-called Rashba-Bychkov (RB) effect that arises from the potential gradient induced by broken inversion symmetry was believed to be the main origin of these spin-polarized electronic states. However, the spin texture of most ALMs are different from that caused by the ideal RB effect. Due to the high impact of the spin-polarized electronic states of 2D materials in not only spin-related fundamental science but also in applications since they are the key concepts to realize future semiconductor spintronics devices, much efforts have been made to elucidate the origin of these peculiar spin textures. So far, the deviations in spin texture from the ideal one have been attributed to be induced by perturbation, such as entanglement of spin and orbital momenta. In this review, we first illustrate how the symmetry of the ALM's atomic structure can affect the spin texture, and then introduce that various spin textures, ranging from the RB-type and symmetry-induced type to spin textures that cannot be explained based on the origins proposed so far, can be simply induced by the orbital angular momentum. This review aims to provide an overview on the insights gained on the spin-polarized electronic states of ALMs and to point out opportunities for exploring exotic physical properties when combining spin and other physics, e.g. superconductivity, and to realize future spintronics-based quantum devices.

The layered two-dimensional material ${\mathrm{MoTe}}_{2}$ in the ${T}_{d}$ crystal phase is a semimetal which has theoretically been predicted to possess topologically nontrivial bands corresponding to Weyl fermions. Clear experimental evidence by angle-resolved photoemission spectroscopy (ARPES) is, however, lacking, which calls for a careful examination of the relation between ground state band structure calculations and ARPES intensity plots. Here we report a study of the near-Fermi-energy band structure of ${\mathrm{MoTe}}_{2}({T}_{d})$ by means of ARPES measurements, density functional theory, and one-step-model ARPES calculations. Good agreement between theory and experiment is obtained. We analyze the orbital character of the surface bands and its relation to the ARPES polarization dependence. We find that light polarization has a major effect on which bands can be observed by ARPES. For $s$-polarized light, the ARPES intensity is dominated by subsurface Mo $d$ orbitals, while $p$-polarized light reveals the bands mainly derived from Te $p$ orbitals. Suitable light polarization for observing either an electron or hole pocket are determined.

This study evaluated the performance of a new O3 /H2 O2 mixed gas sterilization instrument for killing microorganisms and inactivating bacterial endotoxin at low temperatures. Sterility assurance level was achieved by an over 6-log reduction of Geobacillus stearothermophilus ATCC 12980, and the decimal reduction value was 0.77 min in sterilization mode. A reduction of over 3 logs in Limulus amebocyte lysate coagulation activity of purified endotoxin from Escherichia coli was observed after treatment in endotoxin-inactivation mode. The same inactivation ability was observed when treating dried bacterial cells. Biomaterials made of polymer or metal did not exhibit cytotoxicity after gas exposure at O3 concentrations below 200 ppm. As the results of human cell-based pyrogen testing, significant amounts of endotoxin that were over the limit for medical devices contacting cerebrospinal fluid (2.15 EU/device) were detected on scissors washed with a washer-disinfector and sterilized with ethylene oxide or autoclaving. In contrast, endotoxin decreased to 0.29 ± 0.05 EU/device after O3 /H2 O2 mixed gas sterilization in endotoxin-inactivation mode. Compared to conventional gas sterilization methods, O3 /H2 O2 mixed gas has high sterilization ability and a strong capacity to inactivate endotoxin. It is expected that this sterilization technology will improve the safety of reusable medical devices and utensils for regenerative medicine.

The electrons in 2D systems with broken inversion symmetry are spin-polarized due to spin-orbit coupling and provide perfect targets for observing exotic spin-related fundamental phenomena. We observe a Fermi surface with a novel spin texture in the 2D metallic system formed by indium double layers on Si(111) and find that the primary origin of the spin-polarized electronic states of this system is the orbital angular momentum and not the so-called Rashba effect. The present results deepen the understanding of the physics arising from spin-orbit coupling in atomic-layered materials with consequences for spintronic devices and the physics of the superconducting state.

Current pharmacotherapies for voiding dysfunctions are in need of improvement. Lysophosphatidic acid (LPA) is a phospholipid that contracts the urethra by activating type 1 LPA receptors (LPA1). However, the role of LPA1 in regulating urethral tonus during urine voiding which primarily affects the voiding function has not been investigated. To elucidate the role of LPA1 in the regulation of urethral tonus during urine voiding, we investigated the effects of ASP6432, a novel LPA1 antagonist, and the α1-adrenoceptor antagonist tamsulosin on urethral perfusion pressure (UPP) at the filling phase (UPPbase) and the minimum UPP at the voiding phase (UPPnadir) in anesthetized rats under isovolumetric conditions. We further evaluated the effects of ASP6432 and tamsulosin on voiding dysfunction characterized by changes in post-void residual urine (PVR) and voiding efficiency (VE) induced by the nitric oxide synthase inhibitor Nω-nitro- L -arginine methyl ester (L-NAME) in conscious rats using single cystometry. ASP6432 dose-dependently decreased UPPbase and UPPnadir, while tamsulosin reduced UPPbase but did not change UPPnadir. ASP6432 dose-dependently suppressed the L-NAME-induced increase in PVR and decrease in VE, whereas tamsulosin did not affect either PVR or VE. We demonstrate that ASP6432 reduced UPPnadir and ameliorated L-NAME-induced voiding dysfunction, neither of which were affected by tamsulosin. Our study results suggest that LPA1 has a significant role in regulating urethral tonus during urine voiding, and highlight the potential of ASP6432 for improving voiding dysfunctions associated with various lower urinary tract diseases.

Current pharmacotherapies for lower urinary tract symptoms associated with benign prostate hyperplasia (LUTS/BPH) are in need of improvement. Lysophosphatidic acid (LPA) is a phospholipid with various biologic functions. However, its exact role in the lower urinary tract and its target receptor subtype have not been fully elucidated. We investigated the role of LPA and the type 1 LPA receptor (LPA1) in urethral/prostatic contractile function and prostate cell proliferation by pharmacologically characterizing ASP6432 (potassium 1-(2-{[3,5-dimethoxy-4-methyl-N-(3-phenylpropyl)benzamido]methyl}-1,3-thiazole-4-carbonyl)-3-ethyl-2,2-dioxo-2λ6-diazathian-1-ide), a novel LPA1 antagonist. ASP6432 exhibited potent and selective antagonistic activity against LPA1 in cells expressing LPA receptor subtypes. In isolated rat tissue strips and anesthetized rats, ASP6432 concentration-/dose-dependently inhibited LPA-induced urethra and prostate contractions. In addition, in anesthetized rats, ASP6432 maximally decreased the urethral perfusion pressure (UPP) in the absence of exogenous LPA stimulation by 43% from baseline, whereas tamsulosin, an α1-adrenoceptor antagonist, reduced UPP by 22%. Further, in human prostate stromal cells, ASP6432 significantly and concentration-dependently suppressed LPA-induced bromodeoxyuridine incorporation. These results demonstrate a pivotal role for LPA and LPA1 in the regulation of urethral tonus and prostate cell proliferation. The potent urethral relaxation and inhibition of prostatic stromal cell growth indicate the potential of ASP6432 as a novel therapeutic agent for LUTS/BPH.

Spin-momentum locking is essential to the spin-split Fermi surfaces of inversion-symmetry broken materials, which are caused by either Rashba-type or Zeeman-type spin-orbit coupling (SOC). While the effect of Zeeman-type SOC on superconductivity has experimentally been shown recently, that of Rashba-type SOC remains elusive. Here we report on convincing evidence for the critical role of the spin-momentum locking on crystalline atomic-layer superconductors on surfaces, for which the presence of the Rashba-type SOC is demonstrated. In-situ electron transport measurements reveal that in-plane upper critical magnetic field is anomalously enhanced, reaching approximately three times the Pauli limit at $T = 0$. Our quantitative analysis clarifies that dynamic spin-momentum locking, a mechanism where spin is forced to flip at every elastic electron scattering, suppresses the Cooper pair-breaking parameter by orders of magnitude and thereby protects superconductivity. The present result provides a new insight into how superconductivity can survive the detrimental effects of strong magnetic fields and exchange interactions., This is a post-peer-review, pre-copyedit version of an article published in Nature Communications. The final authenticated version is available online at: http://dx.doi.org/10.1038/s41467-021-21642-1

The layered van der Waals antiferromagnet MnBi$_2$Te$_4$ has been predicted to combine the band ordering of archetypical topological insulators such as Bi$_2$Te$_3$ with the magnetism of Mn, making this material a viable candidate for the realization of various magnetic topological states. We have systematically investigated the surface electronic structure of MnBi$_2$Te$_4$(0001) single crystals by use of spin- and angle-resolved photoelectron spectroscopy experiments. In line with theoretical predictions, the results reveal a surface state in the bulk band gap and they provide evidence for the influence of exchange interaction and spin-orbit coupling on the surface electronic structure., Revised version

Reduction methods of the jet flow associated with simulated blast waves by blast wave simulators are investigated by computational simulations. First, the cause of the jet flow is discussed. After that, the influence of the nozzle angle and the volume of the driver section on the jet flow are investigated. The obtained results show that the jet flow is caused by vortices which are generated at the edge of the nozzle and that the jet can be reduced by decreasing the driver section. Furthermore, the nozzle with the moderate angle reduces the jet flow near the nozzle exit and the nozzle with the widest angle reduces the jet flow far from the nozzle exit. These results indicate reducing the driver section and using the proper nozzle angle according to the distance from the nozzle exit are effective for reducing the jet flow.

A proper understanding on the charge mobility in organic materials is one of the key factors to realize highly functionalized organic semiconductor devices. So far, however, although a number of studies have proposed the carrier transport mechanism of rubrene single crystal to be band-like, there are disagreements between the results reported in these papers. Here, we show that the actual dispersion widths of the electronic bands formed by the highest occupied molecular orbital are much smaller than those reported in the literature, and that the disagreements originate from the diffraction effect of photoelectron and the vibrations of molecules. The present result indicates that the electronic bands would not be the main channel for hole mobility in case of rubrene single crystal and the necessity to consider a more complex picture like molecular vibrations mediated carrier transport. These findings open an avenue for a thorough insight on how to realize organic semiconductor devices with high carrier mobility.

Self-assembled organic molecules can potentially be an excellent source of charge and spin for two-dimensional (2D) atomic-layer superconductors. Here we investigate 2D heterostructures based on In atomic layers epitaxially grown on Si and highly ordered metal-phthalocyanine (MPc, M = Mn, Cu) through a variety of techniques: scanning tunneling microscopy, electron transport measurements, angle-resolved photoemission spectroscopy, X-ray magnetic circular dichroism, and ab initio calculations. We demonstrate that the superconducting transition temperature (Tc) of the heterostructures can be modified in a controllable manner. Particularly, the substitution of the coordinated metal atoms from Mn to Cu is found to reverse the Tc shift from negative to positive directions. This distinctive behavior is attributed to a competition of charge and spin effects, the latter of which is governed by the directionality of the relevant d-orbitals. The present study shows the effectiveness of molecule-induced surface dopin...

We have studied the electronic structures of quasi-two-dimensional buckled honeycomb silicon (BHS) saturated by atomic hydrogen and fluorine by means of first-principles calculations. The graphene-like hexagonal silicon with chair configurations can be stabilized by atomic hydrogen and fluorine adsorption. Together with a magnetic ground state, large spin–orbit coupling (SOC) of BHS saturated by hydrogen on either side (Semi-H-BHS) indicated by the band splitting of σ bond at Γ point in the Brillouin zone is attributed to the intermixing between the density of states of hydrogen atoms and π bonds of unpassivated Si2 around the Fermi level. The Zeeman spin splitting is most likely caused by the internal electric field induced by asymmetric charge transfer.

In/Si(111)-( 7 × 3 ) is an atomic layer superconductor formed by an In double layer on Si(111). The size of its circular Fermi surface becomes smaller by the adsorption of copper-phthalocyanine (CuPc) molecules till a coverage of 1.0 monolayer, and then larger at higher coverage. This means that it is possible to control the amount of hole doping, and therefore to tune the energy of the band by CuPc adsorption. By comparing the change in transition temperature ( T c ) reported in “Nano Lett. 17 (2017) 2287”, whose reports the manipulation of T c by CuPc adsorption, and the behavior of the Fermi surface observed in the present study, we conclude that both the increase of T c till a CuPc coverage of 1.0 ML and its decrease from 1.0 to 2.0 ML have strong correlations with the amount of hole doping from CuPc to In/Si(111)-( 7 × 3 ).

Bladder dysfunctions associated with benign prostatic hyperplasia are not sufficiently alleviated by current pharmacotherapies. Lysophosphatidic acid (LPA) is a phospholipid with diverse biological effects. LPA modulates prostate and urethral contraction via the type 1 LPA (LPA1) receptor, suggesting the potential of the LPA1 receptor as a therapeutic target. However, the role of LPA and the LPA1 receptor in bladder function has not been studied in vivo. We investigated the effects of LPA and the novel LPA1 receptor antagonist ASP6432 (potassium 1-(2-{[3,5-dimethoxy-4-methyl-N-(3-phenylpropyl)benzamido]methyl}− 1,3-thiazole-4-carbonyl)− 3-ethyl-2,2-dioxo-2λ6-diazathian-1-ide) on the micturition reflex in conscious rats using cystometry. Intravenous infusion of LPA decreased the micturition interval and threshold pressure with no apparent changes in baseline pressure or maximum intravesical pressure. ASP6432 inhibited the LPA-induced decrease in MI. In contrast, ASP6432 had no effect on the LPA-induced decrease in threshold pressure. Similarly, ASP6432 had no effect on either baseline pressure or maximum intravesical pressure. We also evaluated the effect of ASP6432 on the urinary frequency induced by the nitric oxide synthase inhibitor L-Nω-nitro arginine methyl ester (L-NAME). Intravenous L-NAME administration decreased the micturition interval. ASP6432 dose-dependently reversed the L-NAME-induced decrease in micturition interval. Our findings demonstrate for the first time that LPA causes bladder overactivity in rats. ASP6432 inhibited the LPA- and L-NAME-induced decrease in micturition interval, suggesting a significant role for the LPA1 receptor in regulating the functional capacity of the bladder. Our results also suggest the potential of ASP6432 as a novel therapy for the treatment of bladder dysfunction associated with lower urinary tract diseases.

The characteristic electronic structure of low-dimensional Ag structures on semiconductor, i.e., Si(111)-?3 × ?3-Ag superstructure and Ag quantum well state (QWS), were used to explore the interaction between two-dimensional electron gas and a metal-organic molecule, Fe-phthalocyanine (FePc), using angle-resolved photoelectron and X-ray absorption (XAS) spectroscopies. The characteristic surface states of the Ag low-dimensional (LD) system close to the Fermi level (EF), produced either by an excess of Ag atoms on the Si(111)-?3 × ?3-Ag superstructure or by confinement near the surface as in Ag-QWS, are actively involved in the charge reorganization at the FePc/Ag(LD) interfaces. In the first case, the surface state S1 undergoes a change in its binding energy (BE) and an increase in its electron population; in the latter, the diameter of the Fermi map of the surface state (SS) decreases by 50% suggesting the reduction of its electron population. The two FePc/Ag(LD) systems manifest interface states located at dissimilar BE and with different FePc orbital character as established by photon- and polarization-dependent photoemission measurements. (Figure Presented).

The electronic structure of the Sb 2 Te 3 (0 0 0 1) surface exhibits a spin–orbit split surface state in a local energy gap of the projected bulk valence band continuum. We investigate this surface state by high-resolution angle-resolved photoemission spectroscopy (ARPES), spin-resolved ARPES and relativistic one-step photoemission calculations. At low wave vectors the dispersion and spin splitting are well-captured by the predictions of the Rashba model for a two-dimensional electron system. With increasing wave vectors, however, the surface state dispersion becomes more complex and the spin splitting size exhibits an unusual non-monotonic evolution. These deviations from the Rashba model arise from the influence of bulk continuum states near the edge of the projected gap. The spin polarization of the surface state remains intact despite the coupling to bulk states.

Metal/semiconductor hybrid systems are attractive for integrating spintronic devices on current semiconductor technology. This paper investigates the potential of Tl/Si(111), a system with an unoccupied surface state within the silicon band gap, which forms fully spin-polarized valleys at the $\overline{\mathrm{K}}$ and ${\overline{\mathrm{K}}}^{\ensuremath{'}}$ points close to the Fermi level. Our key findings are the robustness of the system against contamination and the possibility to dope the system such that the fully spin-polarized valleys become metallic. This establishes Tl/Si(111) as possessing all necessary key properties for spintronic applications.

The norlignan (NorL) is a class of secondary metabolites, which occurs in the heartwood (hW) of certain softwood species. Although the NorL is often assumed to be secondarily altered (e.g., oxidized and/or polymerized in the hW over time), the formation and the chemical structure of oxidized/polymerized products remained unclear. In this study, we focused on the question whether an NorL oligomer/polymer exists in the hW of Cryptomeria japonica. First, NorL model polymers were prepared by horseradish peroxidase-catalyzed oxidation and their chemical structures were investigated by size exclusion chromatography-high-performance liquid chromatography (SEC-HPLC), nuclear magnetic resonance (NMR), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Second, methanol (MeOH) extracted from the hW of C. japonica was fractionated, and one of the fractions contained NorL polymers as demonstrated by its chromatographic and spectrometric data in comparison with those of model polymers. Third, five kinds of agatharesinol (AGA) model dimers were synthesized and their chemical structures were determined. 13C-NMR signals corresponding to the model dimer structures were observed in the NMR spectrum of the natural polymer fraction. In summary, an NorL polymer was found in the hW of C. japonica, and its preliminary chemical structure was proposed for the first time.

Research concerning nano-materials (metal-organic frameworks (MOFs), zeolites, mesoporous silicas, etc.) and the nano-scale, including potential barriers for the particulates to diffusion to/from is of increasing importance to the understanding of the catalytic utility of porous materials when combined with any potential super structures (such as hierarchically porous materials). However, it is difficult to characterize the structure of for example MOFs via X-ray powder diffraction because of the serious overlapping of re- flections caused by their large unit cells, and it is also difficult to directly observe the opening of surface pores using ordinary methods. Electron-microscopic methods including high-resolution scanning electron microscopy (HRSEM) have therefore become imperative for the above challenges. Here, we present the theory and practical application of recent advances such as through-the-lens detection systems, which permit a reduced landing energy and the selection of high-resolution, topographically specific emitted electrons, even from electrically insulating nano-materials.

Atomic and valence-band electronic structures of a recently discovered epitaxial silicon oxynitride (SiON) layer on a 6H-SiC(0001) surface were investigated with x-ray diffraction (XRD) and angle-resolved photoemission spectroscopy (ARPES). The atomic structure optimized by XRD analysis well agrees with a previous low-energy electron diffraction analysis and a first-principles calculation. Band dispersions of surface states observed by ARPES can be explained by the previous calculation. Interface states intrinsic to the SiON layer were not observed above the valence-band maximum of SiC, but a diffuse, non-dispersive state was found by ARPES. Its origin is suggested to be a by-product of graphite-like clusters formed on the SiON layer during heat treatment.

The atomic structures of the Bi/Si(111)-( 3 × 3 ) reconstructed surfaces obtained at different adsorbate coverages were studied by dynamical low-energy electron diffraction (LEED) I–V analysis. The experimentally obtained I–V curves of the β-Bi/Si(111)-( 3 × 3 ) surface, which is formed by a Bi coverage of 1 ML, showed good agreement with the curves calculated for the milk stool model, a model proposed in the literature. In contrast to this result, the I–V curves of the α-phase obtained at a coverage of 1/3 ML do not agree with those reported in early LEED studies. We found that the I–V curves reported in the former LEED studies resemble closely to the results obtained for the surface on which the β and α-phases coexist. Based on the obtained I–V curves, we propose a more reliable structural model for the α-phase, and present the way to determine the presence of a high quality α-phase by using LEED.

We studied the thickness dependence of electronic structure and molecular orientation of neutral, square planar, diamagnetic diradical metal complex, bis( o -diiminobenzosemiquinonate) nickel(II) complexes (Ni(DIBSQ) 2 ), thin films grown on a SiO 2 substrate by using ultraviolet photoelectron spectroscopy in combination with metastable atom electron spectroscopy. We observed that the small hole-injection barrier of 0.46 eV for the monolayer film, and the barrier increases continuously with the film thickness and becomes larger than the electron-injection barrier. We further found that molecules are oriented with their long-axes nearly perpendicular to the surface both in the monolayer and multilayer films independent of the film thickness.

The thickness-dependent electronic structures of Dy silicide films grown on a Si(1 1 1) surface have been investigated by angle-resolved photoelectron spectroscopy. Two ( 1 × 1 ) periodic bands, both of them cross the Fermi level, have been observed in the silicide films formed by Dy coverages of 1.0 monolayer and below, and more than five ( 3 × 3 ) periodic bands have been observed in thicker films. Taking the ( 2 3 × 2 3 ) periodic structure of Dy atoms in the submonolayer silicide film into account, the periodicity of the two metallic bands indicate that they mainly originate from the orbitals of Si atoms, which form a ( 1 × 1 ) structure. Of the ( 3 × 3 ) periodic bands observed in thick films, four of them are well explained by the folding of the ( 1 × 1 ) bands into a ( 3 × 3 ) periodicity. Regarding the other band, the three ( 3 × 3 ) periodic bands would originate from the electronic states related to the inner Si layers that form a ( 3 × 3 ) structure, and the one observed in the 3.0 ML film only might originate from the electron located at the interface between bulk Si and the Dy silicide film.

Surface and bulk structural changes in LiNi0.8Co0.2O2 were observed during electrochemical reactions using synchrotron X-ray scattering and a restricted reaction plane of two-dimensional (2D) epitaxial-film electrodes. The bulk structural changes confirmed lithium diffusion through the (110) surface, which is perpendicular to the 2D edges of the layered structure. No (de)intercalation reaction was observed through the (003) surface in the voltage range of 3.0−5.0 V. However, intercalation proceeded below 3.0 V, which indicates unusual three-dimensional lithium diffusion in the 2D structure in the overlithiated state. Structural changes at the electrode surface were different from those in the bulk. Contact with the liquid electrolyte caused an abrupt deformation of the surface crystal lattice, followed by restructuring upon applying a cell voltage. These slow reconstruction processes were dependent on the crystal lattice orientations. The reaction mechanism of the intercalation electrodes for lithium batt...

This article describes the origins of the width of the highest occupied molecular orbital (HOMO) state observed in the ultraviolet photoemission spectra (UPS) of thin organic semiconductor films. Although much research has been performed on the electrical properties of organic devices, a lot of crucial problems still remain. Among these problems, the charge mobility in organic semiconductor systems is one the most important subjects to be elucidated. In order to discuss the mobility, it is essential to understand both the intermolecular interaction and the electron-molecular vibration coupling. Experimental measurements of the energy band dispersion give information about the intermolecular interaction, and experimental detection of the HOMO hole-vibration coupling is indispensable to comprehend impacts of the electron-vibration coupling on the hole transport. Since most of the information is hidden behind the finite bandwidth of the HOMO, only careful UPS measurements can provide information on these important phenomena related to charge carrier dynamics. In this article, we summarize our recent challenges on UPS measurements of organic thin films, which give the band dispersion of the HOMO and the HOMO hole-vibration coupling, and discuss the origins of the UPS bandwidth that relates to the charge carrier dynamics.

We have studied the temperature-dependent electronic states of a copper-phthalocyanine (CuPc) monolayer film adsorbed on a graphite substrate by using metastable-atom electron spectroscopy and ultraviolet photoelectron spectroscopy. The CuPc molecules, which are flat-lying at room temperature, become tilted and condensed at temperatures below 130 K. Taking the temperature-dependent transition reported in the literature into account, we conclude that the transition observed in the present study originates from the change in the correlation between the molecule–substrate and the intermolecular interactions.

A totally anisotropic peculiar Rashba-Bychkov (RB) splitting of electronic bands was found on the Tl/Si(110)-(1×1) surface with C_{1h} symmetry by angle- and spin-resolved photoelectron spectroscopy and first-principles theoretical calculation. The constant energy contour of the upper branch of the RB split band has a warped elliptical shape centered at a k point located between Γ[over ¯] and the edge of the surface Brillouin zone, i.e., at a point without time-reversal symmetry. The spin-polarization vector of this state is in-plane and points almost the same direction along the whole elliptic contour. This novel nonvortical RB spin structure is confirmed as a general phenomenon originating from the C_{1h} symmetry of the surface.

Structure changes of LiNi 0.5 Mn 0.5 O 2 were detected at the electrode/electrolyte interface of lithium cell using synchrotron X-ray scattering and two-dimensional model electrodes. The electrodes were constructed by an epitaxial film of LiNi 0.5 Mn 0.5 O 2 synthesized by pulsed laser deposition (PLD) method. The orientation of the film depends on the substrate plane; the 2D layer of LiNi 0.5 Mn 0.5 O 2 is parallel to the SrTiO 3 (1 1 0) substrate ((1 1 0) LiNi 0.5 Mn 0.5 O 2 //(1 1 0) SrTiO 3 ), while the 2D layer is perpendicular to the SrTiO 3 (1 1 1) substrate ((0 0 3) LiNi 0.5 Mn 0.5 O 2 //(1 1 1) SrTiO 3 ). The in situ X-ray diffraction of LiNi 0.5 Mn 0.5 O 2 (0 0 3) confirmed three-dimensional lithium diffusion through the two-dimensional transition meal layers. The intercalation reaction of LiNi 0.5 Mn 0.5 O 2 will be discussed.

We have investigated the surface electronic structure of the Tl induced Si (1 1 1) - (sqrt(3) × sqrt(3)) surface by using angle-resolved photoelectron spectroscopy. Three semiconducting surface sta ...

We have investigated the relation between the intramolecular vibrational modes of pentacene and the charge redistribution at the pentacene–graphite interface by using high-resolution electron-energy-loss-spectroscopy. The three main vibrational peaks shift to lower energies as the pentacene film thickness decreases. In order to discuss this energy shift, we have calculated the vibrational energies of a free pentacene molecule by changing its charge state. We have also calculated the vibrational energies of a pentacene molecule adsorbed on a graphite sheet by changing the pentacene–graphite distance. Taking the experimental and calculation results into account, we conclude that the observed energy shifts result from an intramolecular charge redistribution. The present results indicate that the effect of an intramolecular charge redistribution is essential to discuss the origin of an energy shift observed in a vibrational study of an organic molecule/substrate interface.