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The effect of Pb and La contents on the lattice configuration in La-substituted Pb([Zr.sub.0.65],[Ti.sub.0.35])[O.sub.3] (La-PZT) films is examined and La-PZT films with various La and Pb contents are prepared on Pt/Ti/Si[O.sub.2]/Si substrates by chemical solution deposition (CSD). The studies have shown that excess Pd has prevented the A-site substituent of La ions.

The studies of the reaction mechanism of lanthanum atom with formaldehyde in gas phase are reported. The findings provide insight into early transition metals which aid the dissociation of formaldehyde and the mechanism of its reverse reaction.

Matrix-isolation infrared spectroscopy is used to investigate the reactions of laser-ablated lanthanum and yttrium atoms with carbon monoxide molecules in solid neon. The results have revealed that the C-O stretching vibrational frequencies of MC[O.sup.+] decrease from Sc to La, thus indicating an increase in metal d orbital -> Co [pi]* back-donation in this series.

The lattice defects and residual strain in layered perovskite [La.sub.2]Cu[O.sub.4+[delta]] (LCO) thin films, which are grown on LaSrAl[O.sub.4] and SrTi[O.sub.4] substrates, are investigated by using transmission electron microscopy and electron energy loss spectroscopy. The analysis has shown that the strain in LCO films on both the types of substrates are largely relaxed by the formation of misfit dislocation cores, although the small lattice mismatch is accommodated by elastic strain in the LCO film on the LaSrAl[O.sub.4] (LSAO) substrate.

Two new structure types of compounds containing reduced Ln-iodide clusters were discovered while finding analogues of known [Cs.sub.4][R.sub.6]Z[I.sub.13] and chi-[K.sub.4][La.sub.6]Os[I.sub.14] phases. The magnetism of CsGd[([Gd.sub.6][Col.sub.12]).sub.2] has indicated that there is magnetic coupling between the spins of the electrons in the 4f orbitals of neighboring Gd atoms.

The electronic structure of Pb(sub 1-x)La(sub x)TiO(sub 3) (PLT) compounds for x= 0 to 30 at. % of La is investigated by soft X-ray absorption near edge structure (XANES) at the Ti L(sub 3.2) and O k edges. The results show that although the distortion at the Ti site decreased as Pb atoms were replaced by La atoms, a perfect octahedral symmetry was not visible.

An glassy states is observed from the dc and ac susceptibility measurements in LaMn(sub 0.5)Fe(sub 0.5)O3. The large field-cooled effect and frequency-dependent results indicate a glassy state between T(sub g) and T(sub p') while the relaxation dynamics does not show cooperative relaxation without aging, suggesting the existence of noninteracting clusters of frozen spin.

The precise structural parameters of Bi(sub 3.5)La(sub 0.5)TiO(sub 12), including lattice parameters, atomic positions, thermal parameters, and La occupancies were determined by a combined refinement using both X-ray and neutron powder diffraction data. The refinement results and spontaneous polarization calculation, concluded that the monoclinic model was more suitable than the orthorhombic model as a crystal system of Bi(sub 3.5)La(sub 0.5)Ti(sub 3)O(sub 12) at 298 K.

X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy is used to study the surface properties of La0.7Sr0.3MnO3 thin films prepared by the channel-spark ablation technique. The findings show a surface layer consisting of SrO and SrCo3 of a few angstrom thick, which can significantly influence the spin injection properties at the interfacial region.

Secondary ion mass spectroscopy and photoemission spectroscopy has shown that aliovalent ion substitution of Mg at the La site is not the main source of hole doping and the Fermi level has not shifted even in heavily doped LaCuOSe Mg. The studies have shown that planar defects composed of Cu and Se deficiencies are created in LaCuOSe, which are explained by the existence of a degenerate low-mobility layer and formation of complex Cu and Se vacancy defects with the help of generalized gradient approximation band calculations.

A combination of matrix-isolation infrared spectroscopy and density functional theory studies is employed to study the reactions of yttrium and lanthanum atoms with nitrous oxide in excess argon. The reactions are shown to exhibit a plausible mechanism for the formation of metal monoxide-dinitrogen and OYNN complexes.

The effect of the content of La dissolved in Mg on the transmission of hydrogenated Mg-La films is examined. The studies have shown that with the increase in La:Mg atomic ratio, the transmission has decreased and the short wavelength limit of the transmission spectra has shifted towards the long wavelength side.

The actinide and lanthanide bonding in M[N(EP[Ph.sub.2]).sub.2].sub.3]] and M[N(EPi[Pr.sub.2]).sub.2].sub.3]] is structurally studied using spectroscopic methods and density functional theory calculations. The increased covalency in the M-E bond is found due to increased d-orbital participation, while in An-E bonds it is due to f-orbital participation.

The neutron atomic pair distribution function (PDF) analysis is utilized to study the structural phase transition from the nonconductive monoclinic form to the highly conductive cubic form in [La.sub.2][Mo.sub.2][O.sub.9] (LAMOX), a fast oxygen ion conductor. The study shows that the local structure of the compound leads to a better comprehension of the structure-property correlation in the highly conductive phases.

La(sub 1-x)NaMnO(sub 3+delta) samples with well-defined cation molecularity and oxygen contents (x = 0.05, x = 0.13, and -0.04

Various density functional calculations and theoretical calculations are conducted to study the synthesis and structural characterization of endohedral pyrrolidinodimetallofullerene, La(sub 2) at the rate C(sub 80)(Ch(sub 2))(sub 2)NTrt. The study of the different adducts of C(sub 80) endohedral fullerenes show that the internal rotation of the La atoms is not affected by the fullerene groups, which can be of great importance in the field of nanomaterial science.

The syntheses of electron-precise/deficient alloys, Ln(sub 5-x)Ca(sub x)Ge4 (x= 3.37, 3.66. 3.82 for Ln=La, x= 3.00, 3.20, 3.26 for Ln=Ce), in the metal-rich R5Tt4 Zintl system (R=rare earth metal, Tt= Si, Ge), are reported. The alloys extend the electronic phase width from electron-rich to open-shell electron-deficient region in the metal-rich Zintl system and demonstrate possible occurrence of varied electron deficiencies in Zintl phases without structural changes.

The first structural analysis of the C72 fullerene encapsulating two La atoms, La2@C72, by high-resolution (super 13)C NMR is reported. Unstable species such as metal clusters, carbides, and nitrides can safely be entrapped in several fullerene cages. This shows that the enhoderal hallow space of fullerenes can provide a unique nanometer-scale field for stabilizing unstable species.