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The applicability of one-dimensional kinetic theory model for laser ablation of carbon is examined. The results have shown that in the one-dimensional approximation the surface pressure and the ablation rate are too low and that the ablation rate is restricted most of the time by the kinetic theory limitation on the maximum mass flux that can be obtained in a phase-change process.

(Super 13)C CPMAS NMR is investigated in application to protein samples with a variety of deuteration patterns. Using ubiquitin as a model system, reasonable (super 1)H-(super 13)C CP transfer is observed for the extensively deuterated samples.

A new nonlocal density functional theory characterization procedure, the finite wall thickness model is proposed, for nanoporous carbons, whereby heterogeneity of pore size and pore walls in the carbon is probed simultaneously. The pore size distributions and pore wall thickness distributions of several commercial activated carbons and coal chars, with good correspondence with X-ray diffractions are determined.

Single-walled carbon nanotubes of uniform diameter are grown in cobalt-substituted MCM-41 molecular sieves template. It is proposed that the diameter of the carbon nanotubes grown in MCM-41 catalysts is controlled by the size of the metallic clusters formed in the template.

Carbon-13 MAS refocused INADEQUATE experiments are carried out on the polymer phase of CsC60. The carbon-13 INADEQUATE spectra showed 'remote' cross-peaks between nonbonded pairs of nuclei, which share a common coupling partner.

Research into the charge transport process in self-organized porous carbon networks which have a conductivity behaviour situated between an insulator and a metal is presented. Four different conductivity mechanisms were seen in the temperature range from 4.2 K to 295 K.

Research into carbon-to-carbon identity proton transfer from ketene, allene, thioketene and ketenimine to their respective conjugate anions in the gas phase is presented. It was demonstrated that the acidities are all higher while the barriers are lower than for the corresponding CH3CH=X series.

It is demonstrated that the well-known BCS-McMillan treatment is incapable of describing the behavior of the face-centered cubic (fcc) A(sub 3)C(sub 60) series at large lattice parameters, by preparing and structurally and electronically characterizing Cs-rich fcc A(sub 3)C(sub 60) phases. The stability of the metallic state at the observed low fulleride densities is important for the correlated electron systems and is attributed to the T(sub 1u) orbital degeneracy stabilizing itinerant over localized states.

Research investigating the electronic sizes of several carbon nanotubes is presented. Particular attention is given to the study of chiralides, bond lengths and ends of carbon nanotubes, as well as to calculations of their absorption spectra.

It has been possible to establish the 2D lattice constant of single-walled carbon nanotubes within a bundle by x-ray diffraction in the range from 290 K to 1600 K. There was shrinkage over the whole temperature range.

Calculations of the ground- and excited-state properties of very large polyacetylene oligomers and zigzag carbon nanotubes are presented. It is shown that the computational time scales linearly with the system size for carbon nanotubes, with high accuracy being achieved.

Issues concerning the photodissociation of mass-selected neutral carbon clusters C4, C5 and C6 are discussed. It is established that multiphoton absorption arises over a wide range of photon energies.

X-ray photoelectron spectroscopy has been used in studying molybdenum-containing carbon films. The latter have been fabricated using an electron cyclotron resonance chemical vapor deposition. Results indicate that the atomic fraction of Mo in the films could be modified by altering the CH4/Ar gas flow ratio. For instance, the atomic fraction can be transformed from 15.11% to 0.32% by changing the ratio from 4/20 to 20/10.

Carbon and lithium spectra were obtained from vacuum spark discharges utilizing a grazing-incidence flat-field spectrometer. Hydrogen and helium-like lines were seen in the carbon spectrum, where only the hydrogen-like lines are seen in the lithium spectrum. A pinhole picture was obtained for the carbon plasma and the pinch diameter was measured to be 100 microns from the equal density profile scan of the pinhole photograph. The optical depth and the escape factor were incorporated into the intensity computation of the lines utilizing an effective plasma size of 50 microns.

Small asymmetric and symmetric carbon-sulfur clusters, CnS and SCnS (n = 1-5), were produced by pulsed laser ablation of a carbon/sulfur mixture, deposited in an argon matrix at 12 K, and examined through Fourier transform infrared absorption spectroscopy. Reactions of neutral Cn (n = 1-9) and CmS (m = 6-0) fragments were shown theoretically to be highly exothermic. Data supporting such aggregation reactions in the formation of the clusters was found from isotopomeric band intensities.

Research was conducted to examine the vibrational spectra of isotopically mixed C5-, C7- and C9- carbon cluster anions trapped in Ar matrixes at 12 K. The cluster anions were formed using a dual laser beam technique and studied using infrared spectroscopy. The excellent fit of the experimental and calculated singly 13C-substituted cluster bands has led to the determination of a linear geometry for all three clusters.

Vapor-phase infrared spectra allow the determination of the stereochemistry of carbon-carbon double bonds conjugated with a vinyl group. Cis and trans isomers of unsubstituted 1,3-alkadienes can be differentiated on the basis of the differences observed in the 900-1000 [cm.sup.-1] region (spectra of cis isomers show two bands at 993 and 906 [cm.sup.-1], while those of trans compounds show three absorptions at 998, 949, and 902 [cm.sup.-1]) and the 1590-1650 [cm.sup.-1] region (the C=C stretch bands are observed at 1595 and 1642 [cm.sup.-1] for cis compounds and at 1604 and 1650 [cm.sup.-1] for trans compounds). Compounds bearing [CH.sub.2]=CHC([CH.sub.3])=CH[CH.sub.2-] and [CH.sub.2]=CHC(=[CH.sub.2])-[CH.sub.2]- structural moieties, referred to as [Alpha]- and [Beta]-type compounds, are frequently encountered as natural products. For compounds bearing [Alpha]-type groups, the cis/trans configuration of the trisubstituted double bond can be determined unambiguously. An absorption at 3095-3091 [cm.sup.-1], for the =[CH.sub.2] stretch vibration, is common to both of these groups; however, due to the presence of two =[CH.sub.2] groups, the relative intensity of the band is much higher for [Beta]-type compounds. For [Alpha]-type compounds, a cis configuration at the C-3 carbon atom is characterized by a =[CH.sub.2] wag absorption at 907-906 [cm.sup.-1]. For [Beta]-type compounds and 3E-[Alpha]-type compounds, this band appears at 899-897 [cm.sup.-1]. In addition, a wavy 'fingerprint' pattern with two minima at 1632 (low intensity) and 1595-1594 [cm.sup.-1] (high intensity) is characteristic for [Beta]-type compounds. Our generalizations are based on spectra of cis and trans ocimene, myrcene, and dehydration products of many 3-methyl-1-alken-3-ols. Six isomers of farnesene can be characterized by GC/FT-IR. Furthermore, gas-phase IR allows the determination of the configuration of the trisubstituted double bond at C-3 in [Alpha]-type farnesene congeners. For example, the homo- and bishomofarnesene isomers from Myrmica ants were shown to include a 3Z bond.

Solid-state NMR spectra of natural abundance 13C in reaction centers from photosynthetic bacteria Rhodobacter sphaeroides R-26 was measured. When the quinone acceptors were removed and continuous visible illumination of the sample was provided, exceptionally strong nuclear spin polarization was observed in NMR lines with chemical shifts resembling those of the aromatic carbons in bacteriochlorophyll and bacteriopheophytin. The observation of spin polarized 15N nuclei in bacteriochiorophyll and bacteriopheophytin was previously demonstrated with nonspecifically 15N-labeled reaction centers. Both the carbon and the nitrogen NMR studies indicate that the polarization is developed on species that carry unpaired electrons in the early electron transfer steps, including the bacteriochlorophyll dimer donor P860 and probably the bacteriopheophytin acceptor I. Both enhanced-absorptive and emissive polarization were seen in the carbon spectrum; most lines were absorptive but the methine carbons of the porphyrin ring ([Alpha], [Beta], [Gamma], [Delta]) exhibited emissive polarization. The change in the sign of the hyperfine coupling at these sites indicates the existence of nodes in the spin density distribution on the tetrapyrrole cofactors flanking each methine carbon bridge.

The two electronic states are responsible for the appearance of phosphorescence spectra of C70 in glassy solutions. The solvent, temperature and concentration dependence of the fluorescence and phosphorescence spectra of C70 are analyzed between 4 to 200 kelvin. The intensity of electronic origin is consistent with the vibronically initiated intensity and is susceptible to solvent. The phosphorescence is quenched at 130 kelvin but fluorescence persists at 300 kelvin.

The ratio of protonated to nonprotonated carbons provides an estimate of the average ring size in complex polycyclic aromatic hydrocarbon mixtures such as heavy olds and coal-derived liquids. Two model compounds, six mixtures of known composition, and nine heavy oil samples have been studied by 13C spin lattice relaxation inversion-recovery methods. Spin-lattice relaxation data differentiate protonated and nonprotonated carbons on the basis of relaxation differences arising from direct CH dipolar interactions. The integrated aromatic carbon intensities for a number of partially relaxed spectra were fit to a proposed spin relaxation rate expression. Results indicate that the carbon relaxation rates for both protonated and nonprotonated carbons are consistent, as expected, with the dipolar coupling of carbons to protons. The spin-lattice relaxation rates from nonlinear curve fitting of the composite resonance lines are consistent with experimental data for individual resonance lines in the model compounds and in the mixtures of model compounds involved in this study. The distribution of relaxation times for both carbon types is also estimated from the nonlinear fit of the experimental magnetization data. Simulations of composite magnetization under different conditions and an associated error analysis have been carried out to verify the validity of the composite relaxation expression. Low-temperature experiments were performed to simulate the heterogeneous lines observed in heavy oils and coal-derived liquids and to test the fitting method under heterogeneous line conditions.

The variation in the 0.3 to 2.6 micrometer spectral reflectance properties of carbides, polymorphs and macromolecular organic-bearing materials indicates the existence of different structure and composition. The visible-near infrared spectral shapes and slopes enable the distinction of the different carbon polymorphs such as diamond, carbon black and graphite. The characteristic features observed in the spectra of interstellar molecules can be used to identify the various compounds in the meteorites.

Diamond particles with a diameter of 0.5 micrometers were detected in a system for the measurement of Raman spectra during the growth of carbon films in a hot filament reactor. The Raman spectra was measured during the actual growth of the diamond film in a hot filament chemical vapor deposition (CVD) reactor, using a gated, multichannel detector.

Phytoplankton growth dynamics, physical aggregation, particle size-dependent sedimentation and degradation were combined in a model that depicts the relation between vertical particle flux and primary productivity as a function of seasonal and other intermittent events. The model was shown to be most sensitive to biological variables such as phytoplankton cell size, stickiness and growth pattern. Changes in these biological factors could be the cause of variation in deep-ocean flux.

Research demonstrates the C-H activation during metalation of the N-confused porphyrin tautomers. Data indicate that the C-H activation is brought about via the aerobic metal oxidation promoting the dissociation of an inner-core proton on the pyrrole ring, which changes the N-confused porphyrin conformation to a planar porphyrin ring, forming manganese complexes.

It has been possible to synthesize large-diameter single-walled carbon nanotubes by adding catalyst promotes, using Fe or Co as primary catalyst. Large-scale output of exclusively single-walled carbon nanotubes in high yields is a vital stage in advancing carbon nanotube research.

The room-temperature ESR spectrum of biazafullerenyl (C59N)2 is manifested by a single sharp narrow line when the compound undergoes thermal homolysis. Such a spectrum has been also found to bear an intensity equal to that of a low concentration defect spin, which is about 1 spin per 600 C59N units. The observed spectrum, which carries a g-factor of 2.0004(2), also corresponds to the fraction of the C59N radicals that are formed during the homolytic process.

It is shown that ozone generated by UV light can be used to clean carbon-contaminated synchrotron-radiation optics., The use of ozone combined with ultraviolet light in cleaning synchrotron-radiation optics that have been exposed to carbon contamination is investigated. A film-thickness monitor is used in measuring the speed with which the combined ozone and UV light method cleaned carbon-contaminated graphite and poly(methyl methacrylate) films. Results indicate that the method is effective in cleaning synchrotron-radiation optics.

X-ray diffraction, field ion microscopy and electron spectroscopy were used to analyze carbon films deposited on polycrystalline tungsten foil by laser ion deposition. The resultsshowed that an interfacial phase was formed. The films exhibited diamondlike characteristics. The carbide phase was observed to primarily form on the tungsten substrate.

The vibrational configuration interaction (VCI) methods as implemented in multimode was used to study the equilibrium structure, vibrational spectroscopy and the dissociation energy of the [F.sup.-]-C[H.sub.4] anion complex. The results obtained for potential energy surface (PES) and dipole moment surface (DMS) variational vibrational calculations could be used to obtain converged vibrational energy levels and intensities for future systems.

The [super 13]C-[super 13]C NMR correlation spectrum of Nephila clavipes spider dragline silk fibers, the NMR resonance assignment and the chemical shift from all residue sites are described. The results have shown that glycine and alanine are both present in two distinct structural environments, such as a disordered [3.sub.1]-helical conformation and an ordered [beta]-sheet structure.

A series of [C.sub.3]-symmetric aza-[[beta].sup.3]-cyclohexapeptides with functionally diverse side chains carrying a good functional diversity are prepared. Combined with the highly efficient synthesis of the macrocyclic precursors, this chemical sequence is an attractive route to a large family of aza-[[beta].sup.3]-pseudopeptidic macrocycles.

The synthesis and characterization of the 18-electron Cp*Ru([[kappa].sup.3]-P,C,C') species complex, which has provided access to the 16-electron Cp*Ru([[kappa].sup.2]-P,C) zwitterion by an unprecedented Ru-C([sp.sup.3]) bond cleavage process that is both facile and reversible, is presented. This unusual rearrangement strategy will provide a general method for disclosing a diversity of reactive low-coordinate metal species in situ by way of carbanion hemilability.

Empirical and computational analyses were conducted to determine the intradimer bonding as a 2-electron-4-center (2[e.sup.-]-4c) C-C bonding interaction for [[TCNE].sub.2.sup.2-]. It was revealed that nonconventional bonding demonstrates distinct spectroscopic properties and is diamagnetic.

The spectrum and the predissociation dynamics of C[S.sub.2.sup.+] [C.sup.2][Sigma.sub.g.sup.+) excited from the vibrationally excited intermediate [B.sup.2][SIGMA.sub.u.sup.+] state were investigated. The findings show that the [1+1] and [1+1'] dissociation paths of C[S.sub.2.sup.+] could be, at least, identified by the C[S.sup.+]/[S.sup.+] branching ratios, and it provides the possibility to select the photodissociation products of the C[S.sub.2.sup.+] ion by choosing the excitation wavelength.

A demonstration is made to explain the fact that fullerene fragments and hydrogenated fragmented fullerenes can be synthesized in bulk amount by high-temperature hydrogenation of C(sub 60). Successful synthesis of these species by matrix-assisted laser desorption ionization time-of-flight mass spectrometry and complete speciation of the resultant complex fullerene mixtures by high-resolution field desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry is confirmed.

The first versatile synthetic methodology for the ladder oligo(phenylenevinylene)s (LOPVs) and related pi-electron systems annelated with silicon and carbon bridges is reported. The results demonstrate a distinct effect of the silicon bridges on the fluorescence.

A series of molecules, based on the smallest carbon cluster with one planar tetracoordinate carbon atom, C5(super 2-), are presented. Several global reactivity indexes, molecular scalar fields, and magnetic responses were calculated to know which electronic factors contribute to their stabilization.

UV/vis/NIR absorbance spectra were used to monitor electron transfer between small-molecule redox reagents and carbon nanotubes (CNTs). Results demonstrate facile oxidation and reduction of CNTs provide a way to quantify the population of valence electrons and point to possible applications of CNT in the catalysis of redox reactions.