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It is known that Schiff bases and their metal complexes have many properties in different biological systems and this varies with its structural properties. This paper has described the method for synthesis of Schiff base ligand (SB1) and derived Co (II) complex of this ligand. The synthesized metal complex is characterized by X‐ray diffraction (XRD), field emission scanning electron microscope (FE‐SEM), and Fourier‐transform infrared spectroscopy (FTIR). XRD shows the crystalline state of the complex and Schiff base as well as FE‐SEM shows the surface morphology and FTIR is used to characterize functional groups, bonding types, and nature of complex. [ABSTRACT FROM AUTHOR]

This work demonstrates the synthesis of fcc-Co derived from an isostructural C o 4 N phase. When deposited at high substrate temperature ( T s ) or thermal annealing ( T a ) above 573 K, the out-diffusion of N from fcc- C o 4 N occurs, leaving behind a high purity fcc-Co phase. Generally, Co grows in a hcp structure, and a hcp to fcc-Co transformation can be facilitated at high temperature or pressure. The proposed route by nitridation and diffusion of N not only brings down the transition temperature but an impurity present in the form of hcp-Co can be avoided altogether as well. Oriented C o 4 N (111) thin films were grown using a CrN(111) template on a quartz substrate using dc magnetron sputtering. Samples were grown at different T s or room temperature grown C o 4 N samples were annealed at different T a . Analysis using x-ray diffraction, N K-edge x-ray absorption, x-ray photoelectron, and secondary ion mass spectroscopy confirmed the formation of fcc- C o 4 N or fcc-Co phases. Furthermore, it was found that Co–N bonding and N concentration get significantly reduced at high T s or T a due to exceptionally high N self-diffusion taking place in C o 4 N. Magnetic measurements using ex situ and in situ magneto-optical Kerr effect showed differences in saturation behavior and coercivity of C o 4 N and fcc-Co samples. By combining structural, electronic, and magnetization measurements, it has been observed that a high purity fcc-Co can be conveniently derived from the isostructural C o 4 N aided by an exceptionally high N self-diffusion in C o 4 N. [ABSTRACT FROM AUTHOR]

In this work, we studied atomic self-diffusion and structural phase transformation in a single phase iron mononitride (FeN) thin film deposited at an optimized substrate temperature (Ts) of 423 K. At this Ts, the FeN film exhibits a tetrahedral coordination between Fe and N atoms (ZnS-type structure with a lattice parameter of 4.28 Å). The structure of the FeN film was studied by combining x-ray diffraction with Fe and N K-edge x-ray absorption spectroscopy and conversion electron Mössbauer spectroscopy measurements. Self-diffusion of Fe and N was measured using secondary ion mass spectroscopy depth profiling in trilayer structures: [FeN(50 nm)/ 57 FeN(2 nm)/FeN(50 nm)] and [FeN(50 nm)/Fe 15 N(2 nm)/FeN(50 nm)] deposited on an amorphous quartz substrate using reactive magnetron sputtering. It was found that atomic self-diffusion is strongly associated with thermal stability. Before reaching the phase decomposition temperature, the self-diffusion of N was found to be slower than Fe. Upon phase decomposition, both Fe and N diffuse rapidly, and at this stage, the self-diffusion of N takes over Fe. Within the thermally stable state, slower N diffusion indicates that Fe–N bonds are stronger than Fe–Fe bonds in FeN. This behavior was predicted theoretically and has been evidenced in this work. [ABSTRACT FROM AUTHOR]

Point defects create exotic properties in materials such as defect-induced luminescence in wide-bandgap semiconductors, magnetism in nonmagnetic materials, single-photon emission from semiconductors, etc. In this article, oxygen defect formation in metallic TiN and semiconducting rock salt-(Al,Sc)N is investigated with a combination of first-principles density functional theory, synchrotron-based x-ray absorption spectroscopy (XAS) analysis, and scanning transmission electron microscopy–energy-dispersive x-ray spectroscopy mapping. Modeling results show that oxygen in TiN and rock salt-(Al,Sc)N prefers to be in the defect complex of substitutional and interstitial oxygen (nON + Oi) types. While in TiN, the preferential interstitial sites of oxygen in ON + Oi are at the tetrahedral site, in rock salt-(Al,Sc)N, a split interstitial site along the [111] direction was found to be energetically preferable. Simulations performed as a function of the oxygen partial pressure show that under experimental growth conditions, four oxygen atoms at the substitutional sites of nitrogen (4ON), along with four Ti atoms, decorate around an interstitial oxygen atom at the tetrahedral site (Oi) in the energetically favored configuration. However, in rock salt-(Al,Sc)N, n in nON + Oi was found to vary from two to four depending on the oxygen partial pressure. Theoretical predictions agree well with the experimentally obtained XAS results. These results are not only important for a fundamental understanding of oxygen impurity defect behavior in rock salt nitride materials but will also help in the development of epitaxial metal/semiconductor superlattices with efficient thermionic properties. [ABSTRACT FROM AUTHOR]