Electronic Susceptibility Research Articles

Preparation, Identification and Cancer Inhibitory Activity of a novel Pd (II) complex derived from E)-2-((4, 5-bis(4-methoxyphenyl)-1H-imidazol-2-yl)diazenyl)-5-iodobenzoic acid

The synthesis and spectral identification of metal complex for Pd(II) ion with newfangled heterocyclic azo dye as ligand (E)-2-((4, 5-bis(4-methoxyphenyl)-1H-imidazol-2-yl)diazenyl)-5-iodobenzoic acid (MPIAIBA) have been organized by reaction of diazonium chloride salt solution of 2-amino-5-iodobenzoic acid with imidazole derivatives in alkaline ethanolic solution. Azo dye ligand and its Pd (II) complex have been characterized by 1H-NMR, analytical data, Infrared, Mass spectrum, thermal analysis (TG-DTG), Electronic Spectral Data, molar conductance and magnetic susceptibility. The elemental investigation of the metal complexes validate the stoichiometry of the [Pd(L)Cl] type where L=azo dye ligand. Molar conductance measured results for organized Pd (II) complex showed 1: 1 electrolyte for Pd (II) ion. The azo dye ligand acts a tridentate and coordinates to the palladium ion via nitrogen atom of azo group of heterocyclic imidazole ring, nitrogen atom of azo group and oxygen of carboxyl group. Square planar geometry is suggested for Pd (II) complex. In this investigation, the cytotoxicity of the azo dye ligand and its Pd(II) complex has screened for in vitro, antitumor movement against human hepatocellular carcinoma HepG-2 utilizing MTT examine. The prepared ligand and its Pd(II) complex demonstrated anticancer movement with IC50 values indicated cytotoxicity against malignant growth cell line with IC50=172.3μg/ml, WRI-68 IC50=238.6μg/ml, while Pd(II)-complex demonstrated specific cytotoxicity in contradiction of disease cell line with IC50 =115.0μg/ml; WRI-68 IC50=192.1μg/ml. The outcomes demonstrated that this sort of compounds has a significant part in the hindrance rate of the development of cells of destructive and normal lines.

Third order nonlinear optical properties of DNA-based biopolymers thin films doped with selected natural chromophores

The results of linear and nonlinear optical (NLO) studies on thin films of DNA based biopolymers, doped with natural chromophores extracts of sweet paprika, turmeric as well as curry leaves are reported and discussed. The thin films were obtained by spin coating on glass substrates. The spectroscopy measurements show that the extracts absorb in visible, at different wavelengths, revealing an important π electron conjugation. The nonlinear optical measurements, done by the optical third harmonic generation technique at 1064.2 nm fundamental wavelength, show that the fast, electronic origin third order NLO susceptibility of natural extracts χ(3)(−3ω;ω,ω,ω), is large and comparable or higher than that measured for synthetic counterparts. The largest one in this study was found for the curry leaves extract: (396.9 ± 40) ×10−14 esu.

Syntheses, characterization and chelating properties of guanidobenzimidazole and guanidophosphonatebenzimidazole

The synthesis of guanidine derivatives of benzimidazole namely, guanidinobenzimidazole, (GBM), guanidinophosphonatebenzimidazole, (GPBM), and their chelating properties are reported in this work. The guanidine and phosphonate derivatives were synthesized along with their metal complexes, Fe(II), Co(II), Ni(II) Cu(II) and Zn(II). The ligands were characterized by 1 H NMR, 13 C NMR spectroscopy while both the ligands and the metal complexes were characterized by C.H.N analysis, Percentage Metal Composition, FT-Infrared spectra Analysis , UV–Visible Electronic Spectroscopy and Magnetic susceptibility measurements. The results from the percentage composition of the metals in the complexes suggest that ratio of the metal to ligand is 1: 2 (M: L) where M = Co(II), Ni(II), Cu(II), Fe(II), Zn(II). Thus, the prepared complexes have the general formulae [ML 2 ]. Electronic Spectral analyses indicated the participation of the imidazolic nitrogen atom and the nitrogen in position 12 of the guanidinobenzimidazole ligand in the coordination of the ligand to the metal ions while, the shifts in the position of theν(P=O) absorption band of the phosphonate moiety in the guanidinophosphonatebenzimidazole, (GPBM) ligand from 1265 cm -1 in the free ligand to 1141-1200 cm -1 in the metal complexes suggested that the P=O is most likely involved together with the nitrogen atom in position 12 in the coordination of the metal ions to the guanidinophosphonatebenzimidazole, (GPBM) ligand. The electronic spectral data and the values of the magnetic susceptibility values suggest six coordinate octahedral/ distorted octahedral geometry for all the complexes. Keywords: Characterization, Chelating properties, Guanidine derivatives, Metal Complexes, Synthesis

Charge density wave in LuP2In ( P=Pt , Pd) induced by electron-phonon interaction

We have explored the origin of charge density wave (CDW) instabilities in ${\mathrm{LuPd}}_{2}\mathrm{In}$ and ${\mathrm{LuPt}}_{2}\mathrm{In}$ cubic-Heusler compounds, employing band structure and phonon dispersion calculations based on the ab initio density functional theory. We have found that, despite quite enhanced electronic susceptibilities along $\mathbf{q}=M\ensuremath{-}R$ for both compounds, the phonon softening instability occurs only for ${\mathrm{LuPt}}_{2}\mathrm{In}$ at $\mathbf{q}=M$, as is consistent with experimental result. We have demonstrated that the key factor inducing the CDW in ${\mathrm{LuPt}}_{2}\mathrm{In}$ is neither the Fermi-surface nesting nor the spin-orbit coupling strength but the electron-phonon interaction with large deformation potential at $\mathbf{q}=M$. In the CDW ground state, the Pt cubes are rotated within the $2\ifmmode\times\else\texttimes\fi{}2\ifmmode\times\else\texttimes\fi{}1$ Heusler structure, retaining the mirror symmetry through all Lu-In planes, which results in the suppression of density of states of Pt $d$ band near the Fermi level.

Zeeman magnetic field effect on the thermodynamic properties of armchair and zigzag phosphorene

We evaluate analytically the effect of Zeeman magnetic field on the direction-dependent electronic heat capacity (EHC) and magnetic susceptibility (MS) of phosphorene within the continuum Hamiltonian model and the Green’s function approach. Our findings show the electronic phase transition from semiconductor to semimetal for the spin-up of electrons at strong magnetic fields. We found that the critical thermal energy of EHC along the armchair (AC) direction is larger than the zigzag (ZZ) one. Also, we report an oscillating and decreasing behavior for the heat capacity of the AC and ZZ case, respectively. Furthermore, we showed that a magnetic phase transition occurs from the antiferromagnetic to ferromagnetic in both AC and ZZ directions of unbiased magnetic field-induced phosphorene, provided by the temperature-dependent MS. Finally, we have shown that there is no electronic and magnetic phase transition in both directions when the bias voltage as an electronic perturbation is present. Our remarkable points are useful for future applications of phosphorene in nanoelectronics and optoelectronics.

Probing spin susceptibility of a correlated two-dimensional electron system by transport and magnetization measurements

We report temperature and density dependences of the spin susceptibility of strongly interacting electrons in Si inversion layers. We measured (i) the itinerant electron susceptibility $\chi^*$ from the Shubnikov-de Haas oscillations in crossed magnetic fields and (ii) thermodynamic susceptibility $\chi_{\rm T}$ sensitive to all the electrons in the layer. Both $\chi^*$ and $\chi_{\rm T}$ are strongly enhanced with lowering the electron density in the metallic phase. However, there is no sign of divergency of either quantity at the density of the metal-insulator transition $n_c$. Moreover, the value of $\chi_{\rm T}$, which can be measured across the transition down to very low densities deep in the insulating phase, increases with density at $n<n_c$, as expected. In the absence of magnetic field, we found the temperature dependence of $\chi^*$ to be consistent with Fermi-liquid-based predictions, and to be much weaker than the power-law, predicted by non-Fermi-liquid models. We attribute a much stronger temperature dependence of $\chi_{\rm T}$ to localized spin droplets. In strong enough in-plane magnetic field, we found the temperature dependence of $\chi^*$ to be stronger than that expected for the Fermi liquid interaction corrections.

Thermal, spectroscopic and in vitro antimicrobial analysis of 2, 2′-(2-((carboxymethyl)(2-(2-hydroxyethoxy)-2-oxoethyl)amino)ethylazanediyl)diacetatocobalt(II)/manganese(II) hydrate

Co(II), and Mn(II) complexes using 2,2′-(2-((carboxymethyl)(2-(2-hydroxyethoxy)-2-oxoethyl)amino)ethylazanediyl)diacetato (SCHOEA), derivative of disodium salt of EDTA were synthesized by three stages and characterized by spectroscopic (UV–Visible, FTIR, EPR, 1H NMR) techniques, magnetic susceptibility measurements and thermal studies (TA). Electronic and magnetic susceptibility measurements indicated low-spin octahedral complexes. The FTIR spectra supported the coordination mode of the ligand as hexadentate with the metal ions. Molar conductivity supported the non-electrolytic nature of the complexes. The EPR spectra confirmed the distorted octahedral geometry of the complexes based on the computation of Hamiltonian parameters and the degree of covalency. In vitro antimicrobial activities of the ligand and metal complexes against three bacterial (Enterobacteraerogenes, Micrococcus luteus, Shigellaflexineria) and two fungal species (Candida albicans, Aspergillusflavus) were performed by disc diffusion method which revealed that the complexes are more potent bactericides and fungicides than the ligand.

Collapse of Critical Nematic Fluctuations in FeSe under Pressure

We report the evolution of the electronic nematic susceptibility in FeSe via Raman scattering as a function of hydrostatic pressure up to 5.8GPa where the superconducting transition temperature T_{c} reaches its maximum. The critical nematic fluctuations observed at low pressure vanish above 1.6GPa, indicating they play a marginal role in the fourfold enhancement of T_{c} at higher pressures. The collapse of nematic fluctuations appears to be linked to a suppression of low energy electronic excitations which manifests itself by optical phonon anomalies at around 2GPa, in agreement with lattice dynamical and electronic structure calculations using local density approximation combined with dynamical mean field theory. Our results reveal two different regimes of nematicity in the phase diagram of FeSe under pressure: a d-wave Pomeranchuk instability of the Fermi surface at low pressure and a magnetic driven orthorhombic distortion at higher pressure.

Graphene\u2019s nonlinear-optical physics revealed through exponentially growing self-phase modulation

Graphene is considered a record-performance nonlinear-optical material on the basis of numerous experiments. The observed strong nonlinear response ascribed to the refractive part of graphene’s electronic third-order susceptibility χ(3) cannot, however, be explained using the relatively modest χ(3) value theoretically predicted for the 2D material. Here we solve this long-standing paradox and demonstrate that, rather than χ(3)-based refraction, a complex phenomenon which we call saturable photoexcited-carrier refraction is at the heart of nonlinear-optical interactions in graphene such as self-phase modulation. Saturable photoexcited-carrier refraction is found to enable self-phase modulation of picosecond optical pulses with exponential-like bandwidth growth along graphene-covered waveguides. Our theory allows explanation of these extraordinary experimental results both qualitatively and quantitatively. It also supports the graphene nonlinearities measured in previous self-phase modulation and self-(de)focusing (Z-scan) experiments. This work signifies a paradigm shift in the understanding of 2D-material nonlinearities and finally enables their full exploitation in next-generation nonlinear-optical devices.

Theoretical Investigation of Plutonium-Based Single-Molecule Magnets.

The electronic structure of a plutonium-based single-molecule magnet (SMM) was theoretically examined by means of multiconfigurational electronic structure theory calculations, including spin-orbit coupling effects. All Pu 5f to 5f transitions for all possible spin states were computed, as well as ligand to metal charge transfer and Pu 5f to 6d transitions. Spin-orbit coupling effects were included a posteriori to accurately describe the electronic transitions. The spin-orbit coupled energies and magnetic moments were then used to compute the magnetic susceptibility curves. The experimental electronic structure and magnetic susceptibility curve were reproduced well by our calculations. A compound with a modified electron-donating ligand (namely a carbene ligand) was also investigated in an attempt to tune the electronic properties of the plutonium SMM, revealing a higher ligand field splitting of the 5f orbitals of Pu, which could in turn enhance the barrier against magnetic relaxation.

Electrical and mechanical studies on ferroelectric lithium rubidium sulphate crystals

Slow evaporation method was used to grow single crystals of lithium rubidium sulphate with high transparency. Single crystal X-ray diffraction analysis shows that at room temperature, the crystal belongs to a monoclinic system with the space group [Formula: see text]/[Formula: see text]. Some physical parameters like plasma energy, Penn gap, Fermi energy and electronic polarizability have been evaluated for the grown crystal. The relation between electronic polarizability and diamagnetic susceptibility for the crystal has been established on the basis of Kirkwood’s semiempirical equation. The ac conductivity and dielectric behavior of the grown crystal were systemically investigated as a function of frequency and temperature. The title compound obeys Jonscher’s power law relations: [Formula: see text], with exponent [Formula: see text]. From the conduction study, it is observed that both small and large polarons take part in conduction process, and at low temperature, both the band and hopping mechanisms are responsible for conduction. From impedance and modulus studies, it is observed that only one conduction relaxation is observed in the crystal at low frequency. The activation energy of the dielectric relaxation (0.41[Formula: see text]eV) and that of the conduction ([Formula: see text][Formula: see text]eV) are in agreement, as a result, there is no difference among the conduction and relaxation species at high temperature. Differential scanning calorimetric analysis of the crystal shows three endothermic peaks at 166[Formula: see text]C, 185[Formula: see text]C, and 202[Formula: see text]C, from which various thermodynamic parameters such as [Formula: see text], [Formula: see text] and [Formula: see text] have been calculated. From Vickers hardness test, we have determined the mechanical strength, and other parameters which include fracture toughness, brittleness index, yield strength, and stiffness constant for the crystal.

Synthesis, spectral characterization, quantum chemical calculations, in-vitro antimicrobial and DNA activity studies of 2-(2′-mercaptophenyl) benzothiazole complexes

New ligand (HMPBT) ligand is prepared via condensation of 2-mercaptoaniline and 2-mercaptobenzoic acid in 1:1 ratio. Metal complexes are prepared and characterized by different physical techniques (IR, UV/Vis., 1H NMR, 13CNMR, TGA, DTA, DSC, XRD, magnetic moment and electrical conductance measurements). From the elemental analyses data, the complexes were proposed to have the general formulae [M(MPBT)2] (where M = Co(II), Ni(II), Cu(II) and Zn(II) and MPBT = Ligand. The molar conductance data reveal that all the metal chelates were non-electrolytes. Infrared spectra of the complexes indicate deprotonation and coordination of the thiol SH. It also confirms that nitrogen atom of the benzothiazole group contribute to the complexation. Electronic spectra and magnetic susceptibility measurements as well as quantum chemical calculations reveal square planar geometry for Cu(II) and Ni(II) complexes and tetrahedral geometry for Co(II) and Zn(II) complexes. The activation of thermodynamic parameters are calculated using Coast-Redfern (CR), Horowitz–Metzger (HM), and Piloyan–Novikova (PN). The geometries of the complexes are confirmed using DFT method from DMOL3 calculations and ligand field parameters. The investigated ligand and metal complexes were screened for their in-vitro antimicrobial activities against different types of fungal and bacterial strains. The resulting data assert on the inspected compounds as a highly promising bactericides and fungicides. The binding activities of zinc (II) complex with CT-DNA was investigated using absorption titration, fluorescence spectroscopy and cyclic voltammetry measurements in a Tris-HCl buffer system at pH 7.0. In addition to these methods, gel electrophoresis and viscosity measurements were also carried out to determine DNA-binding activities with zinc (II) complex in a buffer solution. The results indicated that zinc (II) complex interacts strongly with CT-DNA through the intercalative binding mode.

Syntheses, density functional and sparkle PM6 semi empirical theoretical studies of O,O′-dialkyl/alkylenedithiophosphate derivatives of tin(IV) phthalocyanine adducts

Seven new PcSn [S2P(OR)2]2 and PcSn [S2P(OGO)2]2 tin complexes where Pc is phthalocynine, R = Et, n-Pr, ios-Pr and tert-Bu and G = CH2CMe2CH2, CH2CEt2CH2, and CMe2CMe2 were synthesized and characterized by elemental analyses, Molecular weight determinations, IR and 31P spectroscopy. A sudden novel PcSn [SP(OR)2O]2 where R = iso-Pr has been recovered upon the hydrolysis of the complex with R = iso-Pr during recrystallization. Microanalytical and 31P NMR data revealed a 1:2 metal-ligand (O,O′-dialkyl and alkylenedithiophosphate) molar ratio in all complexes. Geometries were fully optimized at the B3LYP functional where the basis sets used were specified as generic basis sets and geometrical structures and electronic properties of the complexes were evaluated. The optimized geometries were confirmed to be minima on the potential energy surfaces through frequency calculations. The validity of the employed level of theory has been established through comparison of the calculated geometrical parameters of 12 with their observed counterparts. Thermodynamic stabilities were assessed through energy calculations. Aromaticity indices, local softnesses and condensed Fukui Functions were evaluated utilizing the optimized geometries at the specified level of theory. The absorption spectra of the complexes have been established using ORCA2.9 package utilizing the predicted optimized wave functions. Complexes proved to have high electronic susceptibilities.

Metal(II) complexes of bioactive aminonaphthoquinone-based ligand: synthesis, characterization and BSA binding, DNA binding/cleavage, and cytotoxicity studies

An aminonaphthoquinone ligand, L, and its metal complexes of general formula [MLCl2] {M = Co(II), Ni(II), Cu(II) and Zn(II)} have been synthesized and characterized by analytical and spectral techniques. Tetrahedral geometry has been assigned to Ni(II) and Zn(II) complexes and square planar geometry to Co(II) and Cu(II) complexes on the basis of electronic spectral and magnetic susceptibility data. The binding of complexes with bovine serum albumin (BSA) is relatively stronger than that of free ligand and alters the conformation of the protein molecule. Interaction of these complexes with CT-DNA has been investigated using UV-Vis and fluorescence quenching experiments, which show that the complexes bind strongly to DNA through intercalative mode of binding (Kapp 105 M−1). Molecular docking studies reiterate the mode of binding of these compounds with DNA, proposed by spectral studies. The ligand and its complexes cleave plasmid DNA pUC18 to nicked (Form II) and linear (Form III) forms in the presence of H2O2 oxidant. The in vitro cytotoxicity screening shows that Cu(II) complex is more potent against MCF-7 cells and Zn(II) complex exhibits marked cytotoxicity against A-549 cells equal to that of cisplatin. Cell imaging studies suggested apoptosis mode of cell death in these two chosen cell lines.

Synthesis, characterization and biological investigations of novel Schiff base ligands containing imidazoline moiety and their Co(II) and Cu(II) complexes

Novel imidazoline based Schiff base ligands L1 and L2 were synthesized from o-phenylenediamine/o-aminophenol with creatinine. The ligands were complexed with Co(II) and Cu(II) by direct reaction with metal salts. The synthesized ligands and the metal complexes were characterized by elemental analysis, FT-IR, 1H NMR, mass, electronic, thermal analyses, conductivity and magnetic susceptibility measurements. The conductivity measurements showed the non-electrolytic nature of the complexes. The thermogravimetric analyses confirmed the presence of lattice and coordinated water molecules in the complexes. The DFT calculations were carried out at B3LYP/6-31G(d,p) level for the determination of the optimized structure of the ligands. The synthesized ligands and the metal complexes were screened for their antimicrobial activity against two gram positive bacteria (Staphylococcus aureus and Bacillus subtilis) and two gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and two fungal strains (Aspergillus niger and Candida albicans). The outcomes revealed that the metal complexes showed pronounced activity than the ligands.

Pairing and chiral spin density wave instabilities on the honeycomb lattice: A comparative quantum Monte Carlo study

Using finite-temperature determinantal quantum Monte Carlo calculations, we re-examine the pairing susceptibilities in the Hubbard model on the honeycomb lattice, focusing on doping levels onto and away from the van Hove singularity (VHS) filling. For this purpose, electronic densities of $0.75$ (at the hole-doping VHS) and $0.4$ (well below the VHS) are considered in detail, where due to a severe sign problem at strong coupling strengths, we focus on the weak interaction region of the Hubbard model Hamiltonian. From analyzing the temperature dependence of pairing susceptibilities in various symmetry channels, we find the singlet $d$+$id$-wave to be the dominant pairing channel both at and away from the VHS filling. We furthermore investigate the electronic susceptibility to a specific chiral spin density wave (SDW) order, which we find to be similarly relevant at the VHS, while it extenuates upon doping away from the VHS filling.

Electro-optic Response in Germanium Halide Perovskites.

Electro-optic materials that can be solution-processed and provide high-crystalline quality are sought for the development of compact, efficient optical modulators. Here we present density functional theory investigations of the linear electro-optic coefficients of candidate materials cesium and methylammonium germanium halide perovskites. As with their lead halide counterparts, these compounds can be solution-processed, but in contrast, they possess the noncentrosymmetric crystal structures needed to provide a linear electro-optic effect. We find substantial electro-optic responses from these compounds; in particular, for the r51 tensor element of CsGeI3, we predict an electro-optic coefficient of 47 pm·V-1 at the communications wavelength of 1550 nm, surpassing the strongest coefficient of LiNbO3 at 31 pm·V-1. The strong electro-optic responses of the germanium compounds are driven by high nonlinear susceptibilities and dynamics of the germanium atoms that ultimately arise from the distorted crystal structures. Alongside the electro-optic coefficient calculations, we provide the frequency responses for the linear and nonlinear electronic susceptibilities.

Polymer complexes. LXX. Synthesis, spectroscopic studies, thermal properties and antimicrobial activity of metal(II) polymer complexes

The monomer 3‐allyl‐5‐(phenylazo)‐2‐thioxothiazolidine‐4‐one (HL) was prepared by the reaction of allyl rhodanine with aniline through diazo‐coupling reaction. Reaction of HL with Ni(II) or Co(II) salts gave polymer complexes (1–8) with general stoichiometries [M(HL)(Cl)2(OH2)2]n, [M(HL)(O2SO2)(OH2)2]n, [M(L)(O2NO)(H2O)2]n and [M(L)(O2CCH3)(H2O)2]n (where M = Ni(II) or Co(II)). The structures of the polymer complexes were identified using elemental analysis, infrared and electronic spectra, molar conductance, magnetic susceptibility, X‐ray diffraction and thermogravimetric analysis. The interaction between the polymer complexes and calf thymus DNA showed a hypochromism effect. HL and its polymer complexes were tested against bacterial and fungal species. Co(II) polymer complex 2 is the most effective against Klebsiella pneumoniae and is more active than penicillin. The results showed that Ni(II) polymer complex 5 is a good antibacterial agent against Staphylococcus aureus and Pseudomonas aeruginosa. Molecular docking was used to predict the binding between the monomer with the receptors of prostate cancer (PDB code: 2Q7L Hormone) and breast cancer (PDB code: 1JNX Gene regulation). Coats–Redfern and Horowitz–Metzger methods were applied for calculating the thermodynamic parameters of HL and its polymer complexes. The thermal activation energy of decomposition for HL is higher than that for the polymer complexes.

Magnetic Field-Enhanced 4-Electron Pathway for Well-Aligned Co3 O4 /Electrospun Carbon Nanofibers in the Oxygen Reduction Reaction.

The sluggish reaction kinetics of the oxygen reduction reaction (ORR) has been the limiting factor for fuel energy utilization, hence it is desirable to develop high-performance electrocatalysts for a 4-electron pathway ORR. A constant low-current (50 μA) electrodeposition technique is used to realize the formation of a uniform Co3 O4 film on well-aligned electrospun carbon nanofibers (ECNFs) with a time-dependent growth mechanism. This material also exhibits a new finding of mT magnetic field-induced enhancement of the electron exchange number of the ORR at a glassy carbon electrode modified with the Co3 O4 /ECNFs catalyst. The magnetic susceptibility of the unpaired electrons in Co3 O4 improves the kinetics and efficiency of electron transfer reactions in the ORR, which shows a 3.92-electron pathway in the presence of a 1.32 mT magnetic field. This research presents a potential revolution of traditional electrocatalysis by simply applying an external magnetic field on metal oxides as a replacement for noble metals to reduce the risk of fuel-cell degradation and maximize the energy output.

Nickel(II) and copper(II) complexes of 2,2’‐bibenzo[d]thiazole: Synthesis, characterisation and biological studies

Benzothiazole moiety has gained a lot of attention because of its importance as essential pharmacophore in the development of metal based drugs. Nickel(II) and copper(II) complexes of a benzothiazole based ligand, 2,2’‐bibenzo[d]thiazole (L1), synthesized by the reaction of benzothiazole‐2‐carbonylchloride and o‐aminothiophenol, is reported. The compounds were characterised by elemental and percentage metal analyses, spectroscopic (FTIR and UV–vis), 1H and 13C NMR, Mass spectra, thermal, magnetic moment and molar conductance analyses. The mass spectra, elemental and percentage metal composition of the metal complexes gave a 2:1 ligand to metal stoichiometric mole ratio. The spectral data showed that the ligand was coordinated to the metal ions through the nitrogen atoms of the benzothiazole moiety. The electronic spectra and magnetic susceptibility measurements showed that the nickel and copper complexes adopted square planar geometries. The ligand and its metal(II) complexes were screened against some drug resistant microbes and were found to exhibit varied degree of antimicrobial activities. The nickel complex was more active compared to ciprofloxacin against Staphylococcus aureus and Bacillus cereus. Similarly, the antioxidant potential of the ligand was evaluated. The ligand is a better ferrous ion chelating agent compared to 1,10‐phenanthroline and 2,2‐bipyridine. The ligand and its complexes exhibited good antimicrobial and Fe2+ chelating properties making them probable compounds of interest in antibiotic and antioxidant drug researches.