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A systematic and comprehensive computational study of the electronic structure of GaN and InN surfaces in various orientations is reported. All the surface states for polar InN that are located above the conduction-band minimum are found and the source of the intrinsic electron accumulation that is universally observed in InN surfaces is explained.

The density functional theory calculations are used to study the geometric and electronic structure of the new polymorph of tantalum oxynitride, [gamma]-TaON, and its structural stability. The results have shown that the new polymorph [gamma]-TaON is metastable and only 20 kJ/mol less stable when compared to the grDund-state [beta]-polymorph.

GaN nanopillar and nanostripe arrays with embedded InGaN/GaN multi-quantum wells (MQWs) are fabricated by holographic lithography and subsequent reactive ion etching. Etch related damage of the nanostructures is successfully healed through annealing of NH3/N2 mixtures under optimized conditions.

A technique based on electrostatic force microscopy in which light is used to change the charge states of the local region in a solid is introduced and demonstrated. This technique provides a unique feature that it could be used to probe local electronic transitions of a solid in a submicron scale and it is also applied to study the local electronic structure in InN epifilms.

The growth and characterization of the structural and mechanical properties of tantalum zirconium nitride (TaZrN) films and the subsequent simulation of these properties using an ab initio calculation based on density functional theory (DFT) within the generalized gradient approximation is reported. Thin films of TaZrN are deposited on Si(111) substrates using unbalanced magnetron sputtering.

The issue of the existence of a family of molecular iron-nitride clusters of higher nuclearity is investigated. The reason for the investigation is to ascertain whether their features would be advantageous in the interpretation of cofactor structural and electronic properties.

The electronic and vibrational structure of the nitride clusterfullerene TM3N@C80 (I) was investigated with the use of cyclic voltammetry, FTIR, Raman, and X-ray photoemission spectroscopy. Finding reveal that thulium in TM3N@C80 (I) had a formal electronic ground state of +3, in contrast to the +2 state found in TM@C82.

The decorative zirconium oxynitride, ZrO(sub x)N(sub y), thin films are prepared by dc reactive magnetron sputtering and their properties are analyzed as a function of the reactive gas flow and are correlated with the observed structural changes. Hardness measurements suggested higher values for the films in the region where larger grains were found along with a dependence of hardness on the residual stress states.

A study was conducted to examine the matrix-seeded growth of narrow-gap nitride nanostructures in nitrogen ion implanted GaAs and InAs. The results suggest that the matrix plays an important role in the nucleation and growth of narrow-gap nitride nanostructures.

Plasma induced damage to n-type GaN is studied by atomic force microscopy and Raman spectroscopy. It was found that the extent of surface roughening is largely dependent on the surface defect density, since preferential sputtering at these sites takes place.

Highly crystalline zinc nitride ([Zn.sub.3][N.sub.2]) thin films are grown by rf magnetron sputtering on quartz substrates and the substrate temperature during growth has affected the crystal quality of the thin films. Temperature-dependent Hall effect measurements of [Zn.sub.3][N.sub.2] films have displayed distinct conduction mechanisms at specific different temperature ranges.

Several plasma analyses are conducted to explain the synthesis, properties and the phase formation of the different sputtered hafnium oxide and oxynitride films. The presence of vacancies is shown to be extremely beneficial for the formation of the cubic structure of the films.

Several capacitance-voltage measurements are conducted to explain the interface existing between the silicon nitride passivations and AlGaN/AlN/GaN heterostructures. A comparative analysis of the different methods employed for the analysis is also presented.

The synchrotron radial x-ray diffraction technique is employed to explain the strength and high pressure behavior observed in the titanium nitride compounds under a nonhydrostatic compression. The maximum uniaxial stress that can be supported by the system is also determined.

The synthesis of the bimetallic diuranium(IV/IV) complexes which feature a single nitride ligand engaged as a linear, symmetric bridge between two uranium centers is described. The study results provide insight into the stability of the U=N=U core across multiple charge states and metallonitrene-like character of U=N=U core.

Several first-principles calculations are conducted to explain the stabilization mechanisms adopted by the different stable oxygen incorporated surface of the III-nitrides. The structures and the electronic properties of these compounds are also analyzed.

The physical properties of InN and related group III-nitride semiconductors and also the electronic structure, carrier dynamics, optical transitions, defect physics, doping disparity and phonon structure are studied. The perspectives and challenges noticed in the developments of new electronic and optoelectronic devices based on InGaN alloys are discussed.

The spectroscopic methods were used to study the electronic structure and optical properties of conducting ternary transition metal nitrides consisting of metals of different groups of the periodic table of elements. The results provide insight into the plasma energy of the fully dense [Ti.sub.x][Ta.sub.1-x]N varying between 7.8 and 9.45 eV and the optical absorption bands manifested due to the N p -> Ti/Ta d interband transition.

The topographical study of the nanoscale structure of the gold nitride surfaces produced by radio frequency (rf) nitrogen plasma etching of thin gold films is presented. This surface has displayed a surface enhanced Raman scattering effect shown with L-alanine and rhodamine-6G.

Theoretical studies are conducted to explore the effect of the dislocation core energy on equilibrium critical thickness values for III-nitrides. The results revealed that 100 nm GaN thick barriers at the interfaces between InGaN/GaN heterostructures are sufficient to prevent the stress fields of the quantum wells from mutual interactions.

X-ray photoelectron spectroscopy and x-ray diffraction are used for examining the structure of nitride containing gold films produced by reactive ion sputtering and nitrogen plasma etching. The differences between the strain and lattice parameters of gold and gold nitride films are seen and explained by the interstitial nitrogen.

Analogous combined experimental and theoretical studies of the group 6 E[triple bond]M[X.sub.3] molecules and a comparison of the triple bonds formed with different pnictides, metals and halogens are reported. The group 6 metal phosphide bond orders are found to be less than the corresponding nitrides as expected for the larger phosphorus valence orbitals.

The new method is designed that is sensitive to the local rearrangement in the N environment and capable of detecting changes in (GaIn)(NAs) quantum well composition and strain state. This method can be applied to understand the blueshift of differently grown and annealed dilute nitride materials.

The article presents a new approach, which utilizes the N...N coupling of different (salen)ruthenium(VI) nitrides for the general synthesis of the (salen)ruthenium(III) complexes. These ruthenium salen complexes are shown to be widely used as the catalysts in different organic transformations.

The synthesis and structural characterization of decorative zirconium oxynitride, Zr[O.sub.x][N.sub.y], films via dc reactive magnetron sputtering and use of 17:3 nitrogen-to-oxygen-ratio gas mixture is described. The variations in composition confirm the existence of four different zones which are correlated to different crystalline structures.

The article presents the impact of water curvature on the full width at half maximum (FWHM) of the x-ray rocking curves ([omega]-scans) observed in the gallium nitride and other crystalline thin films. The dislocation densities of the films is shown to be approximately proportional to the square of the [omega]-FWHM value.

The physical mechanism of pressure-dependent blue-shift of Raman optical phonons is studied. The phenomenon is caused due to bond compression and energy storage exerted by the compressive stress.

The synthesis and characterization of the ferric azido complex and detailed mass spectrometric and theoretical studies of its fragmentation is reported. The findings from the studies provide insight into the free, high-valent iron nitride formed upon oxidative loss of dinitrogen from the azido ligand in the dication [Fe([N.sub.3])].sup.2+] reaction.

The synthesis and isolation of the first non-isolated pentagon rule Dy[Sc.sub.2]N@[C.sub.76] cage is reported. The complex represents the [C.sub.76] fullerenes mixed metal nitride cluster fullerenes.

The effects of selected nitride compounds on the LiN[H.sub.2] + LiH reaction are examined in order to clarify the reaction mechanism of LiN[H.sub.2] with LiH and improve the hydrogen desorption kinetics. The results have shown that the reaction of LiN[H.sub.2] with LiH below 300 degree centigrade is a heterogeneous solid-state reaction controlled by [Li.sup.+] diffusion from LiH to LiN[H.sub.2] across the interface.

The importance of various radical (NO) and nonradical ([N.sub.2]O) reagents in converting a ruthenium(IV) nitride to the same nitrosyl complex is studied. The reactions are shown to be thermodynamically favorable, increasing the spin density of the complexes.

The characterization of a similar multinuclear scandium nitride, [Sc.sub.4][N.sub.4] which shows a cubic tetrahedral structure and fundamental building block for ScN nanoparticles and crystals is reported.

The thermal stability of sputter deposited Hf-aluminate and nitride Hf-aluminate thin films on top of Si (100) are examined. The results show that in both films with a Hf/Al ratio = 0.5 there is suppression of crystallization.

Density-functional theory is used for investigating the structure-property relationship of Cr:AlN by doping up to 5 Cr atoms in large supercells. The results have shown that the segregation of transition metal (TM) dopants is very important in determining the magnetic properties in III-Nitride based diluted magnetic semiconductors (DMS).

The effects of nitrogen incorporation on the composition and the bonding structure of the hydrogenated carbon nitride films are studied. The nitrogenation of the films leads to the formation of different N-H bonding environments, which in spite of highly affecting the bonding structure, does not have a significant effect on the properties of the films.

The structural and optical properties of coupled GaN/[Al.sub.x][Ga.sub.(1-x)]N/GaN systems were investigated by changing Al content x in the [Al.sub.x][Ga.sub.(1-x)]N barrier layer. It is showed that as the Al content was increased in the [Ga.sub.(1-x)]N layer, the strength of the built-ins strain changed according, resulting in noticeable changes in the high-resolution x-ray diffraction (XRXRD) and photoluminescence characteristics.

A study is conducted on the energy spectrum of the traps and thermal stability of store charge by the thermostimulated exoelectron emission method in hydrogenated H and deuterated D oxide-nitride-oxide (ONO) multilayer stack of silicon-oxide-nitride-oxide-silicon (SONOS) nonvolatile memories. Studies reveal that the trap energies are identical for both types of ONO.

The successful use of organic solovothermal environment in which the reaction of copper(II) chloride and sodium azide in nonaqueous superheated toluene or THF leads to copper azide intermediates that decompose to nanocrystalline copper nitride (Cu3N) at moderate temperatures, is described. The toluene system produces more crystalline Cu3N than THF, suggesting that metal azide to metal nitride conversions work bets as solid-solid conversions rather than conventional dissolved single-source precursor solution decomposition traction.

The study describes the extensive analysis of the transport properties of III-nitrides in the presence of electric fields from low to moderately high intensities. The nonlinear transport is characterized and its main properties are discussed and the ultrafast transient is considered.

The stacking faults folding back and forth between basal and prismatic planes (BSFs and PSFs) are observed in a GaN film grown on a vicinal 6H-SiC substrate with an AIN buffer. The origin of these defects lies in the nucleation of PSFs in the AIN buffer layer in the vicinity of I1 steps on the SiC substrate surface.

The investigation of the structural arrangement of the sp(super 2) phase in amorphous unhydrogenated carbon nitride (a-CN(sub x)) films and its effect on their physical properties were conducted. The analysis of these results in terms of the sp(super 2) phase in the layers, takes place when deposition was performed at higher laser intensities.

The study describes the extensive analysis of the transport properties of III-nitrides in the presence of electric fields from low to moderately high intensities. The nonlinear transport is characterized and its main properties are discussed and the ultrafast transient is considered.

The electronic structures and molecular properties of S2N2 as well as the currently unknown chalcogen nitrides Se2N2 and SeSN2 are studied using various ab initio and density functional methods. The computed high-level spectroscopic data will be of considerable value in future efforts aimed at the preparation of the conducting polymers (SeN)(sub x) and (SeNSN)(sub x).

The ab initio (MP2) and density functional theory (DFT) methods are used to examine a series of MN4 compounds, where M is an alkaline-earth cation, and N(sub 4)(super 2-) is a six-pi-electron ring. Structural, natural bond orbital (NBO), and molecular orbital (MO) analyses indicate that the bonding in the BaN4 system has a large covalent character as compared with other MN4 systems.

An analysis on the effect of the strain field originating from a subsurface stressor on the electronic properties of nitride semiconductors is presented. The isotropic elasticity of utilized to determine the strain field in the structures under investigation.

The potential-linearized augmented plane-wave method and the generalized gradient corrections are used for examining the electronic structure and magnetic properties of MnFe3N. The behavior of magnetism with respect to changes in the unit cell volume is discussed.