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Works: 57 works in 59 publications in 1 language and 59 library holdings
Publication Timeline
Most widely held works by WASHINGTON STATE UNIV PULLMAN Dept. of CHEMISTRY
Luminescence in Applied Magnetic Fields( Book )

2 editions published between 1986 and 1989 in English and held by 2 WorldCat member libraries worldwide

External fields (0-6 kG) applied to inorganic complexes of (nd)8 configurations were shown to produce macroscopic changes in luminescence frequencies and lifetimes. Frequency shifts of about 400/cm were observed. A theoretical study of the octaphosphitoplatinum(II) ion was completed that relates the changes in optical properties to the degree of spin-orbit coupling in the anion. A search for complexes of iridium(I) and rhodium(I) possessing energy level schemes propitious for observing large perturbations of optical properties by relatively small external fields was completed and revealed several promising candidates. The technique of thermal modulation spectroscopy was developed and applied to several types of complexes to evaluate them for future magnetic perturbation measurements
Picosecond Flash Photolysis and Spectroscopy: Bis-(4-Dimethylaminodithiobenzel)-Ni(II), (BDN)( Book )

1 edition published in 1974 in English and held by 1 WorldCat member library worldwide

The transient absorption spectrum of an electronically excited dithiene, bis-(4-dimethylaminodithiobenzil)-Ni(II), BDN, was measured with 10 ps temporal resolution and 1 nm wavelength resolution. For a series of 'heavy atom' solvents, both the ground state and the excited state spectra remained constant while the decay kinetics of the excited state absorption, as well as the recovery from ground state bleaching, varied. The excited state spectrum can plausibly be fit by a particular one electron transition between previously calculated molecular orbitals, although this clearly does not prove that these orbitals provide the best description for the excited states. The authors comment on three possibilities within the framework of the ground state virtual orbital picture. The recently developed techniques will be generally applicable in probing the photodynamics of presently intractable molecular species. The significance of the data for laser mode-locking is discussed. (Modified author abstract)
Optical Nonlinearity in Coupled Exciton-Phonon Systems Near Metal Surfaces( Book )

2 editions published in 1991 in English and held by 1 WorldCat member library worldwide

Surface effects on optical bistability and pump-probe processes for coupled exciton-phonon systems are studied theoretically. When a laser beam is directed on an excitron-phonon coupling system inside an optical cavity, the cavity field intensity is investigated as a function of the driving field intensity for various distances between the sample and a metallic surface representing one of the mirrors of the cavity. It is found that the direction of switch of the optical bistability can be controlled by adjusting the distance from the surface. For a strong laser pump field and a weak probe field directed on this system, the pump-field-induced absorption spectrum is investigated for different distances between this sample and the metal surface. It is found that the position and line shape of the spectrum are significantly changed due to the presence of the surface
Structural Electronic Relationships in Polymeric Solids( Book )

1 edition published in 1983 in English and held by 1 WorldCat member library worldwide

The primary objective was to quantify the excited states of metal complexes so that their ultimate roles in photophysical, photochemical, and chemical processes could be assessed. The long-term goal was to arrive at a degree of sophistication such that materials with desired electrooptical properties could be designed at a molecular level and synthesized. A comprehensive study of osmium(II) (5d)6 complexes of D3 symmetry containing N-heterocyclic ligans was completed. The effect of solvents on the interactions of charge-transfer and ligand-field excited states was also quantified. A new series of complexes containing (nd)10 (n = 3,4) filled-shell metal ions was synthesized and studied spectroscopically revealing a new type of low-lying excited state. The structure of a typical example of this class of substances was determined by crystallography. A major accomplishment was the development of a multiple-state model for the lowest excited states of (nd)8 complexes, which was applied to several examples of rhodium(I) and iridium(I) complexes. Compounds of ruthenium(II) with N-heterocyclic tridentate ligands and D2d symmetry were also quantified spectroscopically
Picosecond Internal Conversion in Crystal Violet( Book )

1 edition published in 1973 in English and held by 1 WorldCat member library worldwide

On the basis of measurements made using the second harmonic of a mode-locked Nd(3+) laser, the authors demonstrate that the efficient quenching of the lowest excited singlet state in the dye, crystal violet involves rapid repopulation of the ground state in less than 10 to the -11th power sec. The repopulation time exhibits a cube root dependence on solvent viscosity. They argue that the data are best explained by a deactivation involving direct S(1) to S(0) internal conversion. They suggest that the class of triphenyl and diphenylmethane dyes should prove to be more efficient and versatile bleachable shutters and passive mode-locking elements for laser construction than any dyes currently in use in the visible region of the spectrum. (Modified author abstract)
Synthesis and Spectroscopic Investigation of Inorganic Materials Possessing Unusual Electronic Properties( Book )

1 edition published in 1979 in English and held by 1 WorldCat member library worldwide

A comprehensive program of synthesis, chemical characterization and optical investigation of complexes of (nd)6 configuration possessing charge-transfer (CT) excited states was carried out. Approximately sixty molecules of Ru(II) and Os(II) were examined, a dozen of Ir(III) and six of Pt(IV). Absorption spectra (300 and 77 K), luminescence spectra (77 - 1.5 K) and temperature dependent decay times, quantum yields and emission spectra were examined. Several systems were subjected to intense magnetic fields at low temperatures. Several new luminescent systems useful for photochemical energy donors were discovered. The project carried the laboratory significantly further toward its stated goal of defining the principles by which new substances with potential value as media for electrooptical devices can be designed and synthesized in the laboratory
Structural Dependence of the Luminescence from Bis(substituted- benzenethiol)-(2,9-dimethyl-1,10-phenanthroline)zinc(2) Complexes( Book )

1 edition published in 1989 in English and held by 1 WorldCat member library worldwide

Changes in luminescence spectra and lifetimes of crystalline samples of the title compounds at 77 K are correlated with phase changes of the solids. The ease of conversion among phases is a general property of this class of materials. For bis (benzenethiol)-(2,9-dimethyl-1,10-phenanthroline)zinc (II) complete structure determinations were made of both phases. The attendant changes of the optical properties are ascribed to rotation of the planes of the two thiol rings on a single zinc ion from an approximately perpendicular to a nearly face-to-face conformation as the slowly heated crystal undergoes the phase change. The relevance of these results to the problem of charge-separation in solids is discussed
Luminescent Transition Metal Complexes in Magnetic and Electric Fields( Book )

1 edition published in 1975 in English and held by 1 WorldCat member library worldwide

During the grant period several important developments pushed the laboratory closer to its long term goal of designing materials with predetermined electrooptical properties. New materials were synthesized that were highly luminescent and amenable to spectroscopic investigation. Magnetic switching of luminescence was demonstrated and the effect of external fields on excited states was quantified. Geometrical parameters of transition metal complex excited states were also determined
Effects of Electron-Interface-Phonon Interactions on Magnetopolaronic Impurity Transitions in Quantum Wells( )

1 edition published in 1992 in English and held by 0 WorldCat member libraries worldwide

Electron interactions with interface phonon modes and strictly- confined bulk phonon modes are considered for the first time to calculate the magnetopolaronic effect on the transition energy of a hydrogenic impurity in the quantum well of a double heterostructure. The electron-phonon interaction is treated as a perturbation on a hydrogenic impurity confined in a quantum well under strong magnetic fields. The unperturbed states are obtained by the variational method with trial wave functions constructed on symmetry considerations. It is found that the transition energy, as a function of the applied magnetic field, breaks up into three branches with two interaction gaps occurring at two-level and three-level resonances. The lowest branch lies below the bulk TO energy. These results are found in good agreement with recent experimental data
An Investigation of the Stoichiometry of Na+ Cotransport with Dopamine in Rat and Human Dopamine Transporters Expressed in Human Embryonic Kidney Cells by Paul Diedrich Schumacher( )

1 edition published in 2001 in English and held by 0 WorldCat member libraries worldwide

The neuronal membrane transporter for dopamine (DAT) is a member of the Na+ and Cl dependent family of transporters and concentrates dopamine intracellularly up to 106 fold over extracellular levels. NY is hypothesized to provide the major driving force for this concentrative property. In order to validate the Na+-gradient hypothesis, it must be shown that NY accumulates in stoichiometric amounts along with the substrate
Kinetics of Intersubband Optical Excitation and Photoinduced Electron Transfer in an Asymmetric Double Quantum Well( )

1 edition published in 1992 in English and held by 0 WorldCat member libraries worldwide

Optical excitation of electrons in an asymmetric double quantum well is theoretically examined. The well is biased to align the excited levels and permit resonant electron tunneling. Emphasis is made on the photoinduced transfer of electrons counter to the bias electric field force. Systems with a weak polarization relaxation (dephasing), are studied using the conventional technique of the Schrodinger equation. A density matrix approach is developed to describe optical excitations in the presence of an arbitrary dephasing. Quantum beats, which follow a short-pulse excitation of the double well, are shown to crucially depend on the dephasing. The excitation profiles obtained for cases of different dephasing reveal the full range of tunneling coupling between the wells from completely coherent to incoherent (stepwise)
Polarizabilities of Trans and Cis Polyacetylene and Interactions Among Chains in Crystalline Polyacetylene( )

1 edition published in 1991 in English and held by 0 WorldCat member libraries worldwide

In this paper, we use the semi-empirical Hartree-Fock method, introduced within the finite electric field perturbation approach, to calculate the molecular and pi-system polarizabilities of trans and cis polyene H( -CH=CH- ) nH (n = 3,4,5 ...,18). The result is that for a given n, the order of both molecular and pi-system polarizabilities of polyene is trans> cis. This result is consistent with the order of experimental values of trans and cis hexatriene. When the n increases from 3 to 18, the contribution of pi-system polarizability to the molecular polarizability increases from 45% to 70%. Using these results, we have extrapolated the polarizabilities of both trans and cis polyacetylene. The order is trans> cis. These results and crystal parameters lead to an estimate of the dispersion energies among polyacetylene chains. The result is also E sub disp (trans)> E sub disp (cis)
Cooperative Effects on Transient Spectral Hole Burning( )

1 edition published in 1992 in English and held by 0 WorldCat member libraries worldwide

The nonlinear optical susceptibility is calculated for a system of two closely located bound excitons by treating the test field as a perturbation in pump-probe experiments. The coherence of the superradiance effect on the spectral hole burning is found to be dramatic in the transient regime for both on-resonance and off-resonance pumping
Coefficients of the Second Viscosity in Bulk Liquid Helium( )

1 edition published in 1992 in English and held by 0 WorldCat member libraries worldwide

The coefficients of the second viscosity in bulk liquid helium are evaluated explicitly as a function of temperature via interactions between the anomalous excitation spectrums. The four coefficients of the second viscosity exhibit a T -1 dependence at low temperatures (well below 0.6 K), which is due to three-phonon processes originating from the anomalous dispersion at very low momenta and temperatures
Dynamics of an M-Level Atom Interacting with Cavity Fields. 3. Nonclassical Behavior of the Initially Squeezed Field( )

1 edition published in 1992 in English and held by 0 WorldCat member libraries worldwide

The interaction of an M-level atom with a single-mode of cavity field initially in a squeezed state is investigated in this paper. The time evolution of nonclassical characteristics of the field, such as the field squeezing, antibunching and sub-Poisson distribution, are computed and discussed in detail. It is found that the initial coherent excitation strength has crucial influence on how such nonclassical behavior can be maintained in the propagation of squeezed light
Light-Induced Electron Transfer Counter to an Electric Field Force in an Asymmetric Double Quantum Well( )

1 edition published in 1992 in English and held by 0 WorldCat member libraries worldwide

Electron transfer counter to an electric-field force is predicted for an asymmetrical double quantum well subjected to a dc bias in response to optical (far ir) excitation of an intersubband electronic transition. This transfer exhibits a resonance enhancement when the bias electric field aligns the excited levels in the wide and narrow wells. The transfer effect is driven by the quantum-mechanical delocalization caused by the coherent resonant tunneling which prevails over the electric force. The effect brings about photoinduced increase of the potential difference at the double well and a transient electric current opposite to the direction favored by the bias
Frequency Dependence of Two-Photon Resonances and Damping in Polymers( )

1 edition published in 1991 in English and held by 0 WorldCat member libraries worldwide

For the two photon resonance in the third-harmonic generation (THG) spectrum of trans-polyacetylene, the existing theories can only qualitatively rather than quantitatively explain the experimental data. In this paper a damping mechanism is proposed. It shows that once the excitation-dependent damping is taken into account, the whole experimental spectrum of the THG can be quantitatively interpreted by our theoretical calculations
Percolation Effects on the Decay of Admolecules( )

1 edition published in 1991 in English and held by 0 WorldCat member libraries worldwide

It is well known that, in a two-component particle composite material, the conductivity exhibits singular behavior near a percolation threshold, namely, a composition at which one of the constituents forms a connected path extending throughout the material. As an example, the effective conductivity of a composite material composed of metal and insulator particles varies as (q-q sub c) to the minus t power), near the metal percolation threshold q sub c, where q is the volume fraction of the metal and t is a characteristic exponent which remains to be determined. In addition to static properties, optical properties of the two--component composite material, both linear and nonlinear, have been extensively studied. In general, composite materials have optical properties very different from those of their constituents, especially in the vicinity of the percolation threshold. Effects of percolation on the energy transfer from an admolecule to a two-component granular composite substrate are investigated. The substrate material is a random mixture of a metal and an insulator non-absorptive to the light. The luminescence decay rate of the admolecule near the composite surface is calculated by means of the effective medium theory as a function of the volume fraction of the metallic granules. It is found that the decay rate is greatly enhanced around the dc conduction percolation threshold at low transition frequencies. For high frequencies, the decay rate peaks at a higher volume fraction of the metallic particles, indicating the existence of a 'bulk percolation' threshold
Nature and Role of Marine Exudates in Particle Aggregation in the Sea (SIGMA ARI)( )

1 edition published in 1996 in English and held by 0 WorldCat member libraries worldwide

The overall goal of the project was to determine the importance of dissolved and colloidal exudates in flocculation of algae in the sea. Thus, during the course of algal blooms, we (1) studied bubble-generated, non-living background particles formed from surface active algal exudates, since these particles appear to play a key role in floc formation; (2) determined the molecular size distribution and composition of exocellular saccharides; and (3) related changes in exopolysaccharide composition and concentration (dissolved, colloidal, and surface active substances) to particle concentration and size distribution, to the formation of transparent exopolymer particles (TEP), and to variations in viscosity of the medium, alpha (the sticking coefficient), and microbial activity (i.e., exo-enzymatic hydrolysis, remineralization and synthesis of microbial exudates). This study has provided the first detailed molecular information on particle aggregation in the sea. This information is essential for understanding the molecular mechanisms that cause particles to adhere, and for modeling particle aggregation dynamics in the upper ocean
Ground State Properties of a 3He Impurity in Liquid 4He Monolayers (Preprint)( )

1 edition published in 1991 in English and held by 0 WorldCat member libraries worldwide

We present the results of ground-state energies, radial distribution functions, liquid structure functions and effective interactions for a He impurity in a He background in two dimensions. The hypernetted-chain scheme for the system described by a Jastrow-type wavefunction is used, taking into account the triplet correlations and elementary diagrams up to fifth order. Solving the Euler Lagrange equations for the two-body distribution functions, which contain triplet correlation and elementary diagrams, improves the results considerably. Furthermore, as a He impurity is inserted into the He background the ground- state energy increases, but the equilibrium density decreases from 0.0350 A to the -2nd power to 0.0336 A to the -2nd power. The radial distribution function is broadened, while its maximum is lowered and shifted to the right (the direction of increasing radial distance) due to its larger zero-point energy, with therefore less localization of the He particle. The results are compared with Monte Carlo results and other studies
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English (22)