Electronic structures of imidazolium-based ionic liquids

Electronic structures of ionic liquids formed by 1-buthyl-3-alkylimidazolium ion [C_nmim]⁺ (n = 4 and 8) with various inorganic and organic anions have been investigated by ultraviolet photoemission, X-ray photoemission, inverse photoemission and soft X-ray emission spectroscopies (SXES). The comparison of the calculated density of states with the observed spectra revealed that the molecular orbital energies of these ionic liquids are significantly affected by the electrostatic Madelung potential among the ions. The SXES results clearly show that the both highest occupied and lowest unoccupied states of [C₄mim]⁺PF₆⁻ are derived from the cation as a result of strong Madelung potential. On the other hand, the SXES results show the valence electronic structures of ionic liquids with larger anion molecules, [C_nmim]⁺Tf₂N⁻ and [C_nmim]⁺OTf⁻ are contributed from the both cation and anion.     

Wilsonian RG Analysis of the P-wave Nucleon–Nucleon Scattering Including Pions

We perform a Wilsonian renormalization group analysis for the nucleon–nucleon scattering in the P waves in the nuclear effective field theory including pions, in a similar way to the one done for the S-waves in our previous paper. We emphasize that the one-pion exchange interaction with large momentum transfer is of the same order as the leading contact interaction, so that there is no mismatch of the power counting. It is explicitly shown by obtaining consistent sets of renormalization group equations, that the cutoff dependence generated by the loop diagrams containing pion exchanges can be compensated by the cutoff dependence of the coupling constants of the contact interactions.     

On the classification of weighing matrices and self‐orthogonal codes

We provide a classification method of weighing matrices based on a classification of self‐orthogonal codes. Using this method, we classify weighing matrices of orders up to 15 and order 17, by revising some known classification. In addition, we give a revised classification of weighing matrices of weight 5. A revised classification of ternary maximal self‐orthogonal codes of lengths 18 and 19 is also presented. © 2011 Wiley Periodicals, Inc. J Combin Designs 20:40–57, 2012     

Extremal Self-Dual [50, 25, 10] Codes with Automorphisms of Order 3 and Quasi-Symmetric 2-(49, 9,6) Designs

Five non-isomorphic quasi-symmetric 2-(49, 9, 6) designs are known. They arise from extremal self-dual [50, 25, 10] codes with a certain weight enumerator. Four of them have an automorphism of order 3 fixing two points. In this paper, it is shown that there are exactly 48 inequivalent extremal self-dual [50, 25, 10] code with this weight enumerator and an automorphism of order 3 fixing two points. 44 new quasi-symmetric 2-(49, 9, 6) designs with an automorphism of order 3 are constructed from these codes.     

The ̅K N → π Σ decay threshold effect in 3He(in-flight K –, n) reaction spectrum

The formation of a deeply-bound K?? ^–? pp state by the ³He(in-flight K? ^–, n) reaction is investigated theoretically in a distorted-wave impulse approximation using the Green’s function method. The expected inclusive and semi-exclusive spectra at $p_{K^-} = 1.0$ GeV/c and $\theta_n = 0^{\circ}$ are calculated for the forthcoming J-PARC E15 experiment. We discuss these spectra with some K? ^–-“pp” optical potentials, taking into account the energy-dependence of the imaginary part of the potentials by a phase space suppression factor.     

Quasi-two-dimensional Fermi surfaces and coherent interlayer transport in KFe₂As₂

We report the results of the angular-dependent magnetoresistance oscillations (AMROs), which can determine the shape of bulk Fermi surfaces (FSs) in quasi-two-dimensional (Q2D) systems, in a highly hole-doped Fe-based superconductor KFe2As2 with Tc ≈ 3.7 K. From the AMROs, we determined the two Q2D FSs with rounded-square cross sections, correspond to 12% and 17% of the first Brillouin zone. The rounded-squared shape of the FS cross section is also confirmed by the analyses of the interlayer transport under in-plane fields. From the obtained FS shape, we infer the character of the 3d orbitals that contribute to the FSs.     

Smallness of fundamental groups for arithmetic schemes

The smallness is proved of étale fundamental groups for arithmetic schemes. This is a higher dimensional analogue of the Hermite-Minkowski theorem. We also refer to the case of varieties over finite fields. As an application, we prove certain finiteness results of representations of the fundamental groups over algebraically closed fields.     

Organic electroluminescent device with aromatic amine-containing polymer as a hole transport layer (II): Poly(arylene ether sulfone)-containing tetraphenylbenzidine

Organic electroluminescent devices were fabricated using a poly(arylene ether sulfone)-containing tetraphenylbenzidine (PTPDES) and tris(8-quinolinolato)-aluminum(III) complex, Alq, as the hole transport layer and the electron-transporting emitter layer, respectively. A device structure of glass substrate/indium—tin oxide (ITO)/PTPDES/Alq/Mg : Ag was employed. Hole injection from ITO through the PTPDES layer to the Alq layer and concomitant electroluminescence from the Alq layer were observed. Bright green light with a luminance of 14,000 cd/m² was observed at a drive voltage of 14 V, indicating that the polymer possesses a high hole mobility and a high electron-blocking capability.     

Infrared and XAFS study on structure and transition behavior of zinc stearate

Structure and transition behavior of zinc(II) stearate crystal were investigated by infrared and XAFS spectroscopies. Structure of zinc stearate at room temperature was estimated as follows. From XAFS analysis, the coordination number of the carboxylate groups around the zinc atom was evaluated as 4 and the Zn-O distance as 1.95 A. Based on the infrared spectrum and a normal mode analysis, the conformation of the alkyl chain was confirmed as all-trans and the sub-cell packing was considered as parallel type, and also the coordination form of the carboxylate groups was determined as bridging bidentate type. As increasing temperature, zinc stearate has a solid liquid phase transition at 130 degrees C. At the transition, the alkyl chains goes into liquid like state as reported by Mesubi but the coordination structure was confirmed to be maintained.