Haldia Government College

The low-temperature evolution of the isovector giant dipole resonance (IVGDR) width has been systematically investigated for the 116Te, 120Te, and 128Te nuclei to explore the roles of shell closure, neutron-to-proton ratio, and thermal shape fluctuations in the damping of collective motion. High-energy γ-rays, produced in alpha-induced fusion reactions, were measured using the LAMBDA spectrometer, with angular-momentum selection provided by γ-multiplicity detectors. The experimental γ-ray spectra were analyzed using a statistical-model framework and Bayesian inference method was applied to extract the IVGDR parameters over the temperature range T ≈  0.8-1.5 MeV. Subsequently, a self-consistent nuclear energy-density-functional framework was employed to calculate the IVGDR widths at finite temperature and to interpret the observed temperature dependence. For the near-spherical 128Te nucleus, which lies close to the neutron magic number N=82, a stronger shell-induced inhibition of the evolution of IVGDR width is observed at low temperature compared to 116Te and 120Te. It has been observed that the low-temperature damping mechanism depends strongly on the proximity to shell closure, which can be quantified using a single dimensionless parameter δm (see main text for its definition). A systematic comparison across isotopic chains in different mass regions further confirms that larger values of δm correspond to relatively broader IVGDR widths, whereas variations in isospin asymmetry do not significantly influence the width.

AbstractReliable estimation of the underreported incidence of intimate partner violence (IPV) is essential to understand the true magnitude and public health burden. An integrated data system that combines multiple sources is commonly used to estimate such a hard-to-count population. Motivated by a real-life IPV dataset, we develop a novel Bayesian estimation strategy based on a trivariate Bernoulli model (TBM) under the multiple systems estimation (MSE) framework. The model accounts for the inherent dependencies commonly found between IPV data sources and provides practical interpretations. Simulation studies suggest that the proposed method outperforms existing estimators in terms of absolute error, coverage and robustness under varying dependence structures. The model is applied to analyse a multiple systems IPV dataset from a United States (U.S.) county and reveals that approximately 23% of IPV incidents are not captured by official records. These findings underscore the importance of statistical model-based estimation of the true size of IPV incidents to improve surveillance and evidence-based policy responses.

Abstract Metal–organic semiconductors based on earth-abundant 3d transition metals offer great potential for optoelectronic devices, yet establishing direct structure–property relationships between specific supramolecular networks, electronic structure, and charge transport remains a major challenge. In this work, we address this gap through a combined experimental and theoretical investigation of two new coordination complexes, [Fe(N3L1)(HN3L1)]Cl4.4(H2O) (complex 1) and [Co(HN3L1)(H2O)2Cl]Cl2.3(H2O) (complex 2), derived from the previously unexplored 4-imidazole-2,6-di(pyrazinyl)pyridine ligand. Single-crystal X-ray diffraction reveals extensive supramolecular architectures stabilized by π···π stacking and hydrogen bonding involving lattice water molecules and chloride counterions. Hirshfeld surface analysis and 2D fingerprint plots quantify the dominant intermolecular contacts, while molecular electrostatic potential, Quantum Theory of Atoms in Molecules, and NCI plot calculations confirm significant anion···π and lone-pair···π interactions in the solid state. Optical absorption studies yield band gaps of 2.02 and 2.16 eV for complexes 1 and 2, respectively, positioning them for visible-light applications. Fabricated Schottky barrier diodes (ITO/sample/Au) demonstrate rectifying behavior, with device 1 exhibiting a rectification ratio of approximately 66 and a conductivity of 9.2 × 10–5 S m–1, outperforming device 2 (rectification ratio ∼17, conductivity 1.14 × 10–5 S m–1). Periodic DFT calculations reveal that the superior electrical performance of complex 1 stems from localized intra-gap states associated with the deprotonated imidazolyl moiety, which facilitate charge transport through hopping mechanisms. These findings elucidate the crucial role of molecular packing and ligand deprotonation in tuning charge transport in functional metal–organic materials.

In recent years, the advancement of fluorometric and colorimetric chemosensors for Bi3+ ions has received notable attention from researchers, owing to the pharmacological, environmental, and industrial relevance of Bi3+ ions. In this review, we present a summary of the design strategies, detection mechanisms, and applications of various Bi3+ chemosensors reported since 2016. Here, all these chemosensors are categorized into four categories: (i) rhodamine-based chemosensors, (ii) pyrene-based chemosensors, (iii) naphthalene-based chemosensors, and (iv) miscellaneous chemosensors. Furthermore, the advantages and disadvantages of chemosensors, as well as their future prospects, have also been addressed herein. As far as we are aware, this represents the inaugural review of organic molecule-based chromogenic and fluorogenic Bi3+ chemosensors.

Two new complexes, [Co(N3L)2](NO3)2·6H2O (complex 1) and [Ni(N3L)2](NO3)2·6H2O (complex 2), have been synthesized using the organic heterocyclic chelating ligand N3L [4-(1-methylimidazole)-2,6-di(pyrazinyl)pyridine] and characterized primarily by single-crystal X-ray diffraction. In addition to detailing the crystal structures of these complexes, we highlight their distorted octahedral geometries and diverse supramolecular interactions, including π···π stacking, anion···π interactions, and hydrogen bonding. These interactions play a crucial role in shaping the distinct 1D, 2D, and 3D supramolecular architectures of both complexes. Notably, noncoordinated water molecules assemble into hexameric water clusters (H2O)6, which are key stabilizing factors for the 3D structures in the solid state. To gain deeper insight into these noncovalent interactions, we performed density functional theory (DFT) calculations combined with quantum theory of atoms in molecules (QTAIM) and noncovalent interaction plot (NCIplot) analyses. These studies allowed us to explore the nature of anion···π interactions and hydrogen bonding within the water clusters. Additionally, the electronic properties of the complexes were investigated through electrical characterization of as-fabricated Schottky diodes, revealing their potential applications in Schottky-diode-based electronic devices. Notably, in the Schottky device structure, complex 1 demonstrated superior electrical transport properties compared to complex 2 followed by its lower bandgap, better conductivity, and lower Schottky barrier height. Furthermore, we analyzed the optical properties of the Co complex (complex 1) as a model system using band structure analysis, density of states (DOS), and projected density of states (PDOS) calculations. The superior performance of complex 1 has also been explained with proper theoretical justification.