Synthesis,Structure, Magnetic Properties,and Catalase‐like Activity of Methoxy‐bridged Manganese(III) Coordination Polymer containing Hydrazone based (O,N,O)2‐Donor Ligand

A 1D coordination polymer of manganese(III) with a hydrazone‐based ligand, [Mn₂(L)(μ‐OCH₃)₂(OHCH₃)₂]_n ( 1 ), was synthesized and characterized by elemental analyses and spectroscopic methods {H₄L = bis[(2‐hydroxynaphthalen‐1‐yl)methylene]adipohydrazide}. The crystal structure of 1 was determined by X‐ray crystallography. The two dianionic domains of the ligand adopt trans configuration, and each coordinates in a tridentate mode via the O, N, O′‐donor atoms to a Mn^III ion forming a dinuclear compound. The methoxy ligands provide an asymmetric bridge between two central manganese atoms, which lead to the formation of a 1D coordination polymer. A 2D supramolecular structure is formed by hydrogen bonding interactions between the 1D chains. Although the methoxy ligands are labile, the polymer preserves its oligonuclearity in the solution. Temperature‐dependent magnetic susceptibility studies proved the presence of a weak antiferromagnetic interaction between manganese(III) ions with J = –3.2 cm^–1, which results from axial distortion of the manganese coordination environment. Compound 1 showed catalase‐like activity in disproportionation of H₂O₂.     

A note on sequences not having metric Poissonian pair correlations

Archiv der Mathematik - The purpose of this note is to present a construction of sequences which do not have metric Poissonian pair correlations (MPPC) and whose additive energies grow at rates...     

Slant Lightlike Submanifolds of Indefinite Cosymplectic Manifolds

In this paper, we introduce the notion of a slant lightlike submanifold of an indefinite Cosymplectic manifold. We provide a nontrivial example and obtain necessary and sufficient conditions for the existence of a slant lightlike submanifold. Also, we give an example of a minimal slant lightlike submanifold of R⁹₂{R^{9}_{2}} and prove some characterization Theorems.     

Fourier transform emission spectroscopy of the EΠ-XΣ transition of CaH and CaD

The emission spectra of CaH and CaD have been recorded at high resolution using a Fourier transform spectrometer and bands belonging to the E²Π-X²Σ⁺ transition have been measured in the 20 100-20 700 cm⁻¹ region. A rotational analysis of 0-0 and 1-1 bands of both the isotopologues has been carried out. The present measurements have been combined with the previously available pure rotation and vibration-rotation data to provide improved spectroscopic constants for the E²Π state. The constants ΔG(½) = 1199.8867(34) cm⁻¹, B_e = 4.345032(49) cm⁻¹, α_e = 0.122115(92) cm⁻¹, r_e = 1.986633(11) Å for CaH, and ΔG(½)=868.7438(46) cm⁻¹, B_e = 2.212496(51) cm⁻¹, α_e = 0.036509(97) cm⁻¹, r_e = 1.993396(23) Å for CaD have been determined.     

Plasmonic modulator utilizing three parallel metal-dielectric-metal waveguide directional coupler and elasto-optic effects

We report, for the first time, on the design of a plasmonic modulator working on the principle of the elasto-optic effects in a directional coupling structure, utilizing three parallel metal-dielectric-metal waveguides. We propose to achieve the active switching of the power propagation using the elasto-optic effect and optimize the extinction ratio of the optical modulation. The device is characterized and numerically analyzed using the finite-element-method at the wavelengths of 1.55 μm. For the modulator length of 2.33 μm, the extinction ratio of the modulation is nearly 14 dB, and the calculated attenuation loss is 4.5 dB. The calculated driving voltage is 4.8 V for the given modulator. The effect of the applied voltage on the modulation is also analyzed.     

Density-temperature-softness scaling of the dynamics of glass-forming soft-sphere liquids

We employ the principle of dynamic equivalence between soft-sphere and hard-sphere fluids [Phys. Rev. E 68, 011405 (2003)] to describe the interplay of the effects of varying the density n, the temperature T, and the softness (characterized by a softness parameter ν(-1)) on the dynamics of glass-forming soft-sphere liquids in terms of simple scaling rules. The main prediction is the existence of a dynamic universality class associated with the hard-sphere fluid, constituted by the soft-sphere systems whose dynamic parameters depend on n, T, and ν only through the reduced density n*≡nσ(HS)(T*,ν). A number of scaling properties observed in recent experiments and simulations involving glass-forming fluids with repulsive short-range interactions are found to be a direct manifestation of this general dynamic equivalence principle.     

Dynamical arrest transition in nanoparticle dispersions with short-range interactions

We measure the dynamical arrest transition in a model, thermoreversible, adhesive hard sphere dispersion. At low volume fractions ?, below the critical point, gelation occurs within the gas-liquid phase boundary. For ? slightly below and above the critical concentration, the phase boundary follows the predicted percolation transition. At high ?, it melds into the predicted attractive-driven glass transition. Our results demonstrate that for ? above ～20% physical gelation is an extension of the attractive-driven glass line and occurs without competition for macroscopic phase separation.     

40 GHz mode-beating with 8 Hz linewidth and 64 fs timing jitter from a synchronized mode-locked quantum-dash laser diode

Linewidth narrowing of the radio frequency beat-tones and the optical-modes is experimentally investigated in a ～40 GHz quantum-dash mode-locked laser diode subject to optical injection of 10 GHz pulses. In comparison to the 75 kHz linewidth exhibited by the beat-tones in passive mode-locking conditions, a remarkable reduction to less than 8 Hz is achieved when the laser is under optical injection. From this beat-tone signal, an integrated root-mean-square timing jitter of 64 fs is calculated. In addition, a quadratic profile of the optical linewidth with the wavelength is observed in active locking, reaching a minimum of 1.7 MHz for the longitudinal modes around 1530 nm and progressively increasing to 37.4 MHz for modes at 1525 nm.