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Planar 1,2-naphthalocyanines present four different geometrical isomers of C_4h, C_2v, D_2h and C_s symmetries. In the case of magnesium complexes these four isomers have been isolated and characterized for the first time. The C_4h and C_s isomers of the magnesium complexes have been transformed in two steps into the corresponding lutetium mononaphthalocyanines 1,2-NcLuX.

The electrochemical deposition of magnesium was investigated in ethereal Grignard salt solution with tetraethylammonium bistrifluoro-methanesulfonimidate additive, using cyclic voltammetry, potentiostatic transients, and scanning electron microscope measurements. The voltammograms showed the presence of reduction and oxidation peaks associated with the deposition and dissolution of magnesium. From the analysis of the experimental current transients, it was shown that the magnesium deposition process was characterized as a three-dimensional nucleation. The deposited product obtained from potentiostatic reduction presented a generally uniform and dense film.

An inverse template method that relies on the use of a controlled porous spacer material was implemented to produce periodic magnesium (Mg) foams. Bulk infiltration pressures were varied to determine a processing-property map. The microstructure and mechanical properties of the resulting periodic Mg foams were investigated using optical and scanning electron microscopy (SEM), and compression testing, respectively. SEM was also used to analyze the surface topology of the periodic foams and compare it to the original template material. It was found that the casting pressure has a great effect not only on the success of the infiltration but also the surface roughness and other microstructural features of the foam.

In this study, three types of functionally graded Al₁₈B₄O₃₃/Mg composites which consisted of 2, 3 and 4 layers and where volume fractions of Al₁₈B₄O₃₃ were gradually changing from 0 to 35% were fabricated using squeeze infiltration technique. The mechanical parameters of each layer were measured for the analysis of residual stress. Elastic finite element numerical models were applied to the analysis of thermal residual stress. The analytic results showed that the residual stresses were significantly decreased in the macrointerface with increasing the number of layer.

Magnesium is light, biocompatible and has similar mechanical properties to natural bone, so it has the potential to be used as a biodegradable material for orthopedic applications. However, pure magnesium severely corrodes in a physiological environment, which may hinder its use for in vivo applications. Protective coatings are effective method to delay the corrosion of Mg. In this study, sol-gel and hydroxyapatite (HA) coatings were applied onto the surface of pure magnesium substrates using a biomimetic technique. The corrosion rate of surface-treated substrates was tested. It was found that both types of coatings substantially slowed down the corrosion of the substrate, the 60Ca so-gel and HA coating was more effectively than the 100Si so-gel and HA coating in hindering the degradation of the substrate. Thus, the corrosion rate of magnesium implants can be closely tailored by coating sol-gel then coating apatite thereby monitoring the release of magnesium ions into the body.

Magnesium (Mg) crystal structures are extensively explored using an evolutionary algorithm implemented in the USPEX code. Two structures with simple trigonal and tetragonal symmetries are discovered to possibly exist under high pressure. The stability of these symmetries is determined by elastic constants and phonon spectrum calculations. First-principle calculations are performed to investigate the structural, mechanical and electronic properties of different Mg structures under high pressure (up to 300 GPa). Above 190 GPa, the trigonal structure is more stable than the hexagonal close-packed (HCP) structure. Particularly, the trigonal structure can be considered a compromise between face-centered cubic (FCC) and HCP blocks. Interestingly, the tetragonal structure density is only 95% HCP structure. In addition, the tetragonal structure has strong directional bonding but is less stable than the HCP structure (up to 600 GPa). Pressure significantly changes the electronic properties of both structures although they remain metallic up to 300 GPa.

In this paper, hierarchical surface structures were developed to achieve the superhydrophobicity on AZ31 magnesium alloys. The uniform nodular microstructure was constructed by laser processing, and the subsequent cobalt electrodeposition fabricated a nanostructured needle-like morphology onto the surface nodules. The superhydrophobic surfaces prepared under varied electrodeposition current densities were characterized. When applying 7 mA/cm² current density, the sample revealed the best superhydrophobic performance. The chemical stability of superhydrophobic samples was tested, which confirmed excellent superhydrophobicity was hardly affected by the corrosion environment. The results showed the samples still possessed the hydrophobic ability after tests. The developed fabrication method combines the advantages of laser processing and electrodeposition, which serves as a fast and cost-effective pathway to manufacture superhydrophobic surfaces.

Polycrystalline nickel–zinc ferrites of chemical formula Ni_0.65-xMg_xZn_0.35Fe₂O₄ (x = 0.00 to 0.2 in steps of 0.04) have been prepared by conventional ceramic technique. Calcination and sintering of all samples have been carried out in air atmosphere at 950°C and 1250°C, respectively, followed by natural cooling to room temperature. All the samples were characterized by the X-ray diffraction (XRD) for structure determination. These samples were then investigated for their magnetic and electric properties, including saturation magnetization, Curie temperature, initial permeability measurements and DC electrical resistivity. Porosity was decreased drastically from 15% to 5% showed better quality of the sintered samples. There were increments in initial permeability and DC electrical resistivity throughout the series of samples. Variations in the observed properties as a function of magnesium concentration have been discussed in light of the existing understanding.

The isotope shifts of the $2s{}^2{\mathrm{\text{S}}}_{1/2}$–$2p{}^2{\mathrm{\text{P}}}_J(J=1/2,3/2)$ transitions for the Li-like neutron-rich and neutron-deficient ${}^{21\text{–}32}\mathrm{\text{Mg}}$ isotopes are calculated using the multi-configuration Dirac–Hartree–Fock (MCDHF) method and the relativistic configuration interaction approach. The results provided herein can be employed for the consistency check with the nuclear root-mean-square (rms) nuclear charge radii of the short-lived magnesium isotopes from the experimental isotope shifts using the corresponding transitions. The methods used here could also be applied to other few-electron Li-like systems and the analogous isotope shift results could be obtained.

This work focuses on the analytical study of mechanical and thermal properties of a nanocomposite that can be obtained by reinforcing graphene in magnesium. The estimated mechanical and thermal properties of graphene–magnesium nanocomposite are much higher than magnesium and other existing alloys used in aerospace materials. We also altered the weight percentage of graphene in the composite and observed mechanical and thermal properties of the composite increase with increase in concentration of graphene reinforcement. The Young’s modulus and thermal conductivity of graphene–magnesium nanocomposite are found to be $\ge$165 GPa and $\ge$175 W/mK, respectively. Nanocomposite material with desired properties for targeted applications can also be designed by our analytical modeling technique. This graphene–magnesium nanocomposite can be used for designing improved aerospace structure systems with enhanced properties.

In this paper, kappa and Druyvesteyn distributions of electronic velocity are discussed for non-Maxwellian distribution. For accurate temperature and electron density diagnostics of Magnesium plasma, for the Magnesium VIII ${}^2{P}_{1/2}^0$ to ${}^2{P}_{3/2}^0$ transitions, we calculate kappa averaged collision strengths for $\kappa$ = 2, 3 and 5 and the Druyvesteyn averaged collision strengths for $x$ = 1.5, 2 and 3, for temperature between $5\times 10^4$ and $2.5\times 10^5\mathrm{\text{K}}$. Results indicate that the kappa averaged collision strengths are slightly larger than those for the Maxwellian distribution, and the Druyvesteyn averaged collision strengths are slightly smaller than those for the Maxwellian distribution, furthermore, the averaged collision strengths will be close to those for Maxwellian distribution with increasing $\kappa$ for the kappa distribution and with decreasing $x$ for the Druyvesteyn distribution. The excitation rate coefficients are also calculated for Maxwellian and non-Maxwellian distributions. This discussion will be significant in study of plasma for the non-Maxwellian distribution.

Modification of bioceramics by ion implantation of magnesium (Mg) is of interest as Mg is the fourth abundant cation in the human body. In this work, magnesium was ion-implanted into a ZrO₂ based bioceramic stabilized with Y₂O₃ and Al₂O₃. Both Mg-implanted and unimplanted samples were soaked in a simulated body fluid (SBF) for a period of time. The deposits on the surface of various samples were characterized with scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). We find that the Mg-implanted ZrO₂ shows better bioactivity than the plain bioceramic. These results indicate that Mg-implantation can improve the bioactivity of the ZrO₂ based bioceramic. Mechanisms governing the improvement are discussed in this paper.

AZ91D magnesium alloys with and without dispersed SiC particles were oxidized between 420 and 500°C in air. They oxidized to fine MgO oxide grains containing dissolved ions of Al. Their oxidation rates increased almost linearly, with an increase in the oxidation temperature and time. SiC particles did not oxidize during oxidation, and increased the oxidation resistance of the alloy through diminishing the exposed surface area. With the increase in the amount of the dispersed SiC particles from 5 to 10, and to 20 wt.%, the oxidation resistance progressively increased.

The need of engineered materials with high strength to weight ratio was instrumental for the development of a novel magnesium metal–metal composite with the addition of titanium (reinforcement) and aluminum (alloying element) through disintegrated melt deposition technique. The X-ray diffraction analysis and scanning electron microscopy analysis used to explore the metallurgical insights of the developed magnesium metal–metal composite. Wear tests were carried out with pin-on-disc equipment by varying the input parameters load and sliding velocity over a sliding distance of 2000m. Wear was obtained as the output from the experiments, and the same was analyzed through Pareto analysis of variance, to identify the significant parameters. Also, a fuzzy logic-based model was developed to predict the wear behavior of the metal–metal composite. The wear mechanisms involved in the dry sliding wear behavior were analyzed through worn surface analysis and wear debris analysis.

Magnesium is reinforced with three different weight percentages (5%, 10% and 15%) of SiC particles (200 mesh size) by stir casting technique to fabricate Mg/SiC_p composites. The Scanning Electron Microscope (SEM) images, micro and macro hardness of three different composites are investigated. The comparison of micro and macro hardness clearly shows that increase in the weight percentage of SiC contributed to increase in hardness. However, uniform dispersion of SiC can be achieved while adding 5% SiC in the composite. Then, the Box Behnken experimental design in response surface methodology is employed for machining 3mm diameter hole in the Mg/SiC_p samples using EDM. The second-order model for Material Removal Rate (MRR) and Tool Wear Rate (TWR) are developed with the influencing parameters of weight percentage of SiC, current, pulse on time and pulse off time. The parameter optimization yields maximum MRR and minimum TWR.

In this work, the dry sliding wear behaviors of pure monolithic magnesium and magnesium–titanium dioxide (Mg–TiO₂) composites were studied using pin-on-disc tribometer against an oil-hardened nonshrinking die steel (OHNS) counter-disc with a normal load of 0.5–2kg and a sliding velocity of 1.5–2.5$\mathrm{\text{m}}\cdot {\mathrm{\text{s}}}^{-1}$ with the sliding distance and wear track diameter of 1500m and 90mm, respectively. The pin samples were characterized for their microstructural, nanomechanical and tribological properties such as wear rate, coefficient of friction and wear fractographs. Scanning electron microscopy (SEM) was used to analyze the worn-out surfaces of each pin sample in order to identify the different types of wear and wear mechanisms and the chemical constituents of each element were quantified by energy-dispersive spectroscopy. The influence of TiO₂ reinforcements on the nanomechanical behavior was studied by nanoindentation technique. As compared with pure Mg, the nanoindentation strengths of Mg–1.5TiO₂, Mg–2.5TiO₂ and Mg–5TiO₂ composites were found to increase by 11.9%, 22.2% and 35.8%, respectively, which was due to the addition of TiO₂ particles and also due to the good bonding at the interface of TiO₂ and magnesium particles. From the wear test results, a significant change in wear rate was observed with the change in normal load than that of sliding speed, whereas a significant change in coefficient of friction was noticed with the changes in both normal load and sliding velocity. The dominant wear mechanisms involved under the testing conditions were identified through plotting the contour maps and SEM fractographs. Also, from the fractographs it was noticed that delamination and plowing effect have been the significant wear mechanisms observed during low wear rate of samples, whereas melting, delamination and oxidation wear have been observed during high wear rate of pure Mg and its composites.

The current scenario focuses on lightweight and better energy-absorbing structural materials for critical engineering applications in aerospace, automobiles, marine, electronic, and implant materials for biomedical industries. The magnesium-based syntactic foams are the preferred choice of material in the same category due to their lightweight, higher plateau strength, better damping characteristics, and excellent energy absorption behavior. Many works were reported based on the polymer and aluminum-based syntactic foams and their developments. However, the rapidly increasing interest in magnesium-based syntactic foams and the adoption of the applications are still at a nascent stage. This proposed review work comprehensively insights the magnesium-based syntactic foam; various hollow filler material usages and summarizes the influence of physical and mechanical behavior on processing routes and future research opportunities for applications.

Phenylboronic acid esters of an unsaturated precursor 1,2-dicyano-1,2-bis(2-hydroxy- ethylthio)ethylene and the magnesium porphyrazine derived from it have been prepared either by refluxing a mixture of the reagents in chloroform in the presence of molecular sieve or by solvent-free heating in an oven under reduced pressure. The two novel compounds have been characterized by elemental analysis together with ultraviolet-visible, infrared spectroscopy, proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, boron-11 nuclear magnetic resonance, and mass spectra.

The reduction of magnesium phthalocyanine (MgPc) with 2.2 equivalents of potassium graphite in 1,2-dimethoxyethane (DME) gives [K₂(DME)₄]PcMg(OH)(1) in 67% yield. Compound 1 was structurally characterized using single crystal X-ray crystallography and was found to be a monomeric, heterometallic complex consisting of a μ₃-OH ligand that bridges a [Mg^IIPc^3-]^- anion to two potassium cations solvated by four DME molecules. An absorption spectrum of 1 confirms the Pc ligand is singly reduced and has a 3–charge. The solid-state structure of 1 does not indicate breaking of the aromaticity of the Pc ligand. Compound 1 is only the second Pc^3- complex and the first reduced MgPc to be isolated and structurally characterized.

We designed and synthesized anthryl-disubstituted magnesium tetraethynylporphyrin([{5,15-bis(anthracen-9′-yl)ethynyl}-10,20-bis{(triisopropylsilyl)ethynyl}porphyrinato] magnesium(II)), and applied it as an electron donor to solution-processed bulk heterojunction small molecule organic solar cells. The compound was characterized by single crystal X-ray crystallography as well as UV-vis light absorption spectrum showing the absorption maximum and onset at 700 and 740 nm, respectively. Organic solar cells using this compound and [6,6]-phenyl-C61-butyric acid methyl ester (PC₆₁BM) as electron donor and acceptor, respectively, showed power conversion efficiency of 1.31% at the donor and acceptor ratio of 1:3. The use of pyridine as a coordinating additive increased power conversion efficiency to 1.61%, which was the best among tested additives, THF, pyradine, dioxane, and 1,8-diiodooctane.