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Microprobe Raman spectroscopy is used to investigate the piezospectropic (PS) effect in intergrowth bismuth layer-structure ferroelectric (IBLSF) ceramic [Bi.sub.5]TiNbW[O.sub.15]. The contribution of the probe to the signal is evaluated and an in-depth deconvolution procedure is applied in order to reduce the error introduced by the finite size of the illuminated area.

Laser-ablated Sb and Bi atoms react with hydrogen during condensation in excess hydrogen, neon, and argon to form the SbH and BiH diatomic molecules. The new Group 15 MH2 dihydride radicals and the MH3 trihydrides are observed for Sb and Bi metals.

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.

In situ Raman spectroscopic and synchrotron-based angle dispersive x-ray diffraction methods are used for examining the high pressure behavior of the compound [Bi.sub.12]Si[O.sub.20]. The stability of [Bi.sub.12]Si[O.sub.20] at pressure is discussed with respect to the pressure-induced amorphization described in bismuth-orthosilicate ([Bi.sub.4][Si.sub.3][O.sub.12]) and 'Orthogermanate.

The first detailed study of [super 209]Bi solid-state NMR (SSNMR) spectroscopy of extremely broad central transition powder patterns is reported. The rapidly acquired [super 209]Bi SSNMR spectra at ultrahigh fields, the sensitivity of the [super 209]Bi NMR parameters to the bismuth environment, and the predictive power of theoretically calculated NMR interaction tensors suggested the potential application of [super 209]Bi SSNMR for the characterization of a variety of Bi-containing materials and compounds.

The x-ray diffraction method was used to examine the single crystal structure of the compound [Pb.sub.3][Bi.sub.2][S.sub.6] that undergoes a first-order phase transition at hydrostatic pressure between 3.7 and 4.9 GPa. The reversible phase transition with a preservation of the single crystal is attributed to the stereochemical influence and migration of the [S.sup.2] lone electron pairs of [Pb.sup.II] and [Bi.sup.III].

The dielectric response of the perovskite ceramics (1-x)La([Mg.sub.1/2][Ti.sub.1/2])[O.sub.3]-xBi([Mg.sub.1/2][Ti.sub.1/2])[O.sub.3] ((1-x)LMT-xBMT) is described at radio, microwave and far infrared (FIR) frequency ranges. The characteristic features of the Bi-induced dielectric relaxation and those typical of the ferroelectric relaxors are compared.

The preparation and spectroscopic and amplification properties of Bi-activated, Ga and Al codoped germanium glass is described. The findings from the studies showed that the obtained glass could find potential application as solid-state broadband near-infrared sources and optical amplifiers.

The optical and ultrafast nonlinear optical properties of [Yb.sup.3+] doped sodium borate and bismuthate glasses fabricated by the melt quench technique is reported. The results from z-scan studies showed that the increase in three-photon absorption coefficient with [Bi.sub.2][O.sub.3] concentration is attributed to the highly polarizable nature of [Bi.sup.3+] ions and the nonlinearity is attributed to glass host and the nonbridging oxygen ions.

Several studies are conducted to explain the field emission mechanisms of the bismuth sulfide upright-standing platelets, which are chemically prepared by using the indium-tin-oxide substrate. These platelets are shown to exhibit high values of the turn-on field and current density and hence can be used easily in the manufacture of electronic devices.

The Raman and infrared-reflectivity spectroscopy techniques are employed to study the optical phonon characteristics of the commensurate, as well as incommensurate modulated phases of the [Bi.sub.3]Nb[O.sub.7] ceramic samples. The material is shown to be widely used in the microwave devices, as it exhibits higher quality factor and potential interest in the tetragonal phase.

An attempt to prepare rare-earth ion doped bismuthate (LZBB) glasses without traditional glass formers, lead and cadmium is demonstrated. The studies shed light on making large buck rare-earth ion doped LZBB glasses by avoiding crystallization applied in S- and U-band amplifiers and medical lasers based on the glasses.

Two new mixed-valence complexes were synthesized using pyridylamide ligands. It is found that the dimer [Cu2(pmac)2]OTf and trimer [Cu3(pp(ac)2)2].NaOTf both contain fully delocalized, mixed valence [Cu.sup.1.5][Cu.sup.1.5] moieties.

The Li self-diffusion in rhombohedral [Li.sub.7]Bi[O.sub.6] studied through [super 7]Li stimulated echo NMR that was observed to give microscopic access to long-range transport is reported.

A set of open-chain fully substituted bi-, ter-, and quaterpyrroles bearing analogous substituents in the [alpha]- and [beta]-pyrrolic positions are evaluated as a function of their chain length, subunit number and size of potential conjugation pathway. The results have indicated that the unpaired electron is more delocalized on the pyrroles with a longer conjugation and that the more the unpaired is delocalized, the faster is the electron exchange rate.

The multiferroic properties of [Bi.sub.0.825][Nd.sub.0.175]Fe[O.sub.3] (BNFO) and BFO thin films are analyzed by comparing their crystal structures, leakage current densities, ferroelectricity, Raman scattering spectra and weak ferromagnetism. The Raman spectra has indicated that the ferroelectric distortion of BNFO is less stable than that of BFO due to the weakening of the stereochemical activity of Bi lone electron pair and the change of the corresponding Bi-O bonds.

The mixed ligand complex [Ni[(CMA).sub.2][(im).sub.2][(MeOH).sub.2] (where CMA = 9,10-dihydro-9-oxo-10-acridineacetate ion, im = imidazole), is prepared and its crystal and molecular structure are determined. The spectroscopic and magnetic studies have provided reliable experimental data for determining the electrical structure of the metal enzyme center.

The defect levels in CdTe doped with different Bi concentration are analyzed by low temperature photoluminescence, photoinduced current transient spectroscopy, photoconductivity measurements and optical absorption. The two centers associated with the doping with Bi, a deep level located at [E.sub.v]+0.71 eV and an acceptor center located at [E.sub.v]+0.30eV, are described.

The analysis of the (super 15)N{(super 31)P} rotational echo double resonance (REDOR) data is extended by examining the contribution of interactions between surface phosphorous atoms to the observed (super 15)N REDOR decay. The (super 31)P-(super 31)P dipolar couplings are incorporated and the method is applied to reanalyze the (super 15)N{(super 31)P} REDOR of the lysine side chain approaching the hydroxyapatite (HAP) surface.

A study introduces a simple chemical method to synthesize semimetal bismuth nanoparticles in N,N-dimethylformamide (DMF) by reducing Bi(super 3+) with sodium borohydride (NaBH4) in the presence of poly(vinylpyrroldone) (PVP) at room temperature. The results indicate that PVP serves as an effective capping ligand, which prevents the nanoparticles from aggregation.

Bi(sub 3.15)Nd(sub 0.85)Ti(sub 3-x)W(sub x)O(sub 12) thin films are fabricated on (111)Pt/Ti/SiO(sub 2)/Si and substrates by a chemical solution deposition technique. The grain size, Raman spectra, dielectric, hysteresis loops, switching, leakage current, fatigue, and retention are systemically investigated as a function of the W content.

Organic nanoparticles from a chiral auxilliary, (R)-(+)-1,1'-Bi-2-napthol dimethyl ether (BNDE), with a range of particle sizes from 25 to 100 nm were fabricated through the reprecipitation method. The excitation chirality of the particles displays size-tunability, that is the exciton chirality peak evolves to the low energy side, as the particles grow larger.

The spectroscopic properties and thermal stability of Er(sub 2)O(sub 3) doped Bi(sub 2)O(sub 3)-B(sub 2)O(sub 3)-Na(sub 2)O glasses are tested and a correlation between the content and the B(sub 2)O(sub 3) content and the spectroscopic properties is found. The replacement of B(sub 2)O(sub 3) for Bi(sub 2)O(sub 3) led to the strengthening of the network structure and improved the stability of glass.

Study on the production and thermal stability of photochromic absorption in chromium doped Bi12GeO20 (BGO) is presented. It is observed that doping BGO with chromium introduces a series of over-lapping absorption bands in the 650-1100 nm range.

Glasses with electronic properties intermediate between the ionic and metallic state are obtained. This is achieved by melts of Bi-BiCl(sub 3) and Bi-BiCl(sub 3)-KCl mixtures being rapidly quenched into the glassy state at cooling rates of ~10(super 8) K/s.