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High-resolution x-ray photoelectron spectroscopy of strontium bismuth tantalate films has disclosed distinct chemical states of constituent atoms in fluorite and perovskite crystals. The amorphous and fluorite phases are expressed as a mixture of [Bi.sub.2][O.sub.3] and [Bi.sub.2][O.sub.2], whereas the [([Bi.sub.2][O.sub.2]).sup.2+] component representing the bismuth oxide layer, which is adjacent to the [(Sr[Ta.sub.2][O.sub.7]).sup.2-] block, has predominated in the perovskite phase.

The infrared (IR) transmission, Raman Scattering, magnetic measurement, and electronic resistance measurement are used for studying [La.sub.2-x][Sr.sub.x][Cu.sub.0.94][Mn.sub.0.06][O.sub.4] and [La.sub.2-x][Sr.sub.x][Cu.sub.0.94][Ru.sub.0.06][O.sub.4] systems. The results have shown coexistence and competition between superconductivity and magnetism.

The synthesis and characterization of a series of triazenide complexes of the heavier alkaline earths, Ca, Sr, and Ba is described. The results demonstrated the potential coordination chemistry of the internal nitrogen of the triazenide ligand set.

The Fe valence state of [Sr.sub.2]FeMo[O.sub.6] samples is studied by using site specific x-ray absorption spectroscopy and x-ray magnetic circular dichroism. The chemical changes with time are important for potential applications of [Sr.sub.2]FeMo[O.sub.6] and related transition metal oxides.

The structure, magnetism, and transport in strained epitaxial [La.sub.0.5][Sr.sub.0.5]Co[O.sub.3] (001) films deposited on SrTi[O.sub.3] (001) substrates by reactive dc magnetron sputtering are examined. The results have shown a thin layer at the film/substrate interface with different structural properties to the bulk of the film, as well as a strongly graded magnetic and chemical profile at the film surface due to the significant roughness.

A sequential phase transition is described by using high-resolution synchrotron x-ray scattering in a single crystal [Nd.sub.1/2][Sr.sub.1/]Mn[O.sub.3]. The sequent transition is studied by the formation of different magnetic domains at different temperature ranges as that seen by neutron powder diffraction.

The single-crystal X-ray diffraction technique is employed to explain the synthesis and characterization of a new member of the family of dodecameric oxo clusters, [Sn.sub.12][O.sub.8][(OH).sub.4][(OEt).sub.28][(HOEt).sub.4]. Two different types of trimeric subunits are shown to form the structure of the discussed complex.

[Sr.sup.2+] doping in Ca[Al.sub.2][O.sub.4]:[Eu.sup.2+], [Nd.sup.3] is utilized for detecting that isolated [Ca.sup.2+] vacancies arrayed in the same line with [Eu.sup.2+] and [Nd.sup.3+] along the b-axis in Ca[Al.sub.2][O.sub.4]. The speed of the transportation is determined by the transportation capability of those [Ca.sup.2+] vacancies and the speed has determined the combination of carriers and influences the persistent luminescence properties of Ca[Al.sub.2][O.sub.4]:[Eu.sup.2+], [Nd.sup.3+] as well.

Out-of-band (OOB) radiation emitted from dense tin plasmas generated by a laser is examined for application as an extreme ultraviolet lithography light source. Prominent line broadening due to the Stark effect in the high-density plasma is observed and the expansion velocities of neutral and singly ionized tin atoms are deduced from time-of-flight transients in the spectral emission.

A local nanocrystalline formation in a neodymium doped strontium barium niobate (SBN) glass is obtained under argon laser irradiation. The results have shown that nanocrystals of SBN are created by the laser action confirming that the transition from glass to glass ceramic is completed.

The synthesis and the x-ray diffraction patter, magnetic susceptibility, and electrical resistivity of the orthorhombic phase of SrIr[O.sub.3] is described. The magnetic and electrical properties showed that the orthorhombic SrIr[O.sub.3] perovskite is paramagnetic below 170 K and is metallic above 44 K before a band type metal insulator transition appeared.

Several crystallographic studies are conducted to explain the impact of the randomly existing charge ordered stripes on the magnetotransport properties of [La.sub.0.6][Sr.sub.0.4]Mn[O.sub.3] perovskite, which is substituted with diamagnetic ions at Mn sublattice. The saturation magnetization of the compound is shown to decrease with an increase in the doping concentrations at the Mn sites.

Micro-Raman spectroscopy is used to characterize two common growth-induced defects, including bubble core and cloudiness in ytterbium doped strontium fluoroapatite [Yb.sup.3+]:[Sr.sub.5][(P[O.sub.4]).sub.3]F (Yb:S-FAP) crystals. Several types of impurities are identified that are distributed randomly in the cloudy region, thus leading to improvement of Y-SFAP quality and its optical application.

Raman scattering is used for examining the room temperature phonons of tetragonal [Sr.sub.2]CoW[O.sub.6] and monoclinic [Ca.sub.2]CoW[O.sub.6], [Sr.sub.2]CoTe[O.sub.6] and [Ca.sub.2]CoTe[O.sub.6] double perovskites. The reduced number of bands seen in the Raman spectra is explained and a novel method is presented for describing the phase transitions in terms of the group-subgroup symmetry correlation of these vibrational modes.

Photoemission spectroscopy (PES) and soft x-ray absorption spectroscopy (XAS) are used to investigate the electronic structures of Sr[Mn.sub.1-x][Fe.sub.x][O.sub.3] (0

The electrical properties of ([Pb.sub.0.97][Sr.sub.0.03])([Zr.sub.0.05][Ti.sub.0.95]) (PSZT) are investigated by using a complex impedance spectroscopic technique in order to study the grain and grain boundary. The impedance spectroscopic analysis has showed the presence of both bulk and grain boundary effects in the material and the modulus analysis has indicated the possibility of hopping mechanism for electrical processes in the system with a nonexponential type of conductivity relaxation.

Er(super 3+):SrWO4 crystal of good optical quality was grown by Czochralski technique method. Polarized absorption and emission spectra of Er(super 3+) ions in SrWO4 crystal are investigated.

SrAl2O4: Ln [Ln=Ce(super 3+), Pr(super 3+), Tb(super 3+)] nanocrystals is synthesized by the combustion method. It is found that the resulting SrAl2O4: Ln (Ln= Ce(super 3+), Pr(super 3+), Tb(super 3+)) nanocrystals have reduced and distorted monoclinic lattice compared with bulk materials.

The growth of Sr on n-type Si(001) is studied in detail for coverages between 0 and 1 monolayer (ML) using core level photoemission spectroscopy. Data analysis was carried out by a method that allows accurate determination of the band-bending shifts.

The dependence of hole doping level on the photo control of the (La,Sr)MnO3/SrTiO3 heterojunction is investigated. Phase boundary between metallic and insulating region on the (La(sub 1-x)Srx)MnO3 phase diagram, plays an important role in photo carrier control of the functional heterojunction.

Synchroton x-ray scattering is used to study microstructural changes in epitaxial SrRuO3 thin films grown on SrTiO3(001) during the early stages of growth by pulsed laser deposition. At a very early stage of growth (less than or equal to 110 Angstrom), the film is composed of a single (110) domain only.

A quantitative analysis of the chemical shifts, shielding tensors, spectral intensities and energetic of the solid solutions [Pb,Sr](NO3)2 and [Pb,Ba](No3)2 and discuss their implications for the thermodynamics of ion clustering in such systems is presented. Monte Carlo simulation of the spectral intensities viewed that the ion are slightly clustered in the crystal, which disagrees with a conventional but specious analysis of the dependence of the unit cell volume on composition.

A novel type of highly nanostructured cathodes demonstrating very low polarization resistance, fabricated from [La.sub.0.6][Sr.sub.0.4]Co[O.sub.3] (LSCO) nanotubes by a simple method using the pore wetting technique are described. Results reveal that the area-specific resistance (ASR) of these cathodes is much lower and reaches satisfactory values to be used for technological applications.