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The syntheses and characterization of [(cyclamacetate)FeF]PF6 and the corresponding N-methylated complex [(trimethylcyclamacetate)FeF]PF6 are described. The results show that the difference in spin states between these complexes is a combination of solvation, steric, and electronic effects and that the most important effects are likely steric and electronic.

A description is provided on the photochemistry of O-chlorooxyalyl and O-fluoroformyl-9-fluorenone oxime. Time-resolved step/scan FTIR spectroscopy investigations on fluoroformyl oxide gave evidence of the formation of fluoroformyl radical FCO(super .) which rapidly adds to the solvent acetonitrile, yielding a fluoroformyl-functionalized iminyl radical.

The carbon 1s ionization energies for all of the carbon atoms in benzene molecules are measured by high-resolution photoelectron spectroscopy. A comparison of the ionization energies and proton affinities gives insight into the effects of fluorine as an electron-withdrawing group and as a pi donor, both in the neutral molecular and in response to an added positive charge.

The ARS-E model was used for calculating the intermolecular interaction energy of hexafluorobenzene-benzene. The largest and most negative energy of -5.38 kcal/mol was observed in the slipped-parallel complex.

The collective electronic oscillator (CEO) approach was adopted for calculating the linear absorption and florescence spectra and the oscillator strengths of 2,2',7,7'-tetraphenyl-9,9'-spirobifluorene, 2,2',7,7'-tetrakis(biphenyl-4-yl)-9,9'-spirobifluorene and 2,2',7,7'-tetrakis(9,9'-spirobifluoren-2-yl)-9,9'spirobifluorene. The higher CEO modes with significant oscillator strengths are corresponding to different spiro-centers, intra-branch and inter-branch neutral electronic delocalization.

Quantum scattering calculations for the reaction F + HCI --> HF + CI are performed on ab initio potential energy surface. The shape of the adiabatic potential surface yields to a simple and intuitive interpretation for the rotational enhancement of the rate.

Hydrolysis and condensation of simple trifluorosilanes, HSiF(sub 3) and MeSiF(sub 3), is studied by quantum mechanical methods. The results suggest that the activation energy for hydrolysis by a water dimer is significantly lower than that for hydrolysis by a water monomer.

Photogeneration of C(sub 6)F(sub 5)-C(sub 6)F(sub 4)H from HO-B(C(sub 6)F(sub 5))(sub 3)- and of C(sub 6)H(sub 5)-C(sub 6)F(sub 4)H from C(sub 6)H(sub 5)-B(C(sub 6)F(sub 5))(sub 3)- was studied. The photogeneration of H(sub 2)O.B(C(sub 6)F(sub 5))(sub 3) resulted from irradiation of isoquinolinium hydroxytris(pentafluorophenyl)borate.

A simple spirobifluorene molecule with pseudotetrahedral structure was investigated for its supposed conformational resilience upon adsorption. The molecule stays 'rigid' by keeping one of the original symmetry elements in the two physisorbed states while in an unexpected state, a strong deformation destroyed definitively any symmetry of the molecule.

CaF2(11) surface is used, where atomic resolution force microscopy allows identification of the positions of the Ca(super 2-) and F2 ions in the obtained images to demonstrate that short-range interaction forces can be measured selectively above chemically identified surface site. Combing theoretical and experimental results allows a quantification of the strength and distance dependence of the interaction of a tip-terminating cluster with particular surface ions.

The preparation of the [NBu(sub 4)][Pt(C(sub 6)F(sub 5))(sub 3)L] complexes containing triazene (L), formamidine and 2-aminopyridine was carried out. In formamidine the Pt-H bond interaction is stable enough to be detected in the solution whereas in 2-aminopyridine the Pt-H bond can be observed in crystal but not in solution.

The study of ionization and double ionization spectra of (H(sub 2)O)(sub1-3)F(super -) calculated by ab initio methods with microsolvation of F(super -) is conducted. Results show that the ionization spectrum of the isomer A with C(sub 3) symmetric ground-state geometry is rather similar from the energetical point of view to that of the isomer B with one H-donor-bound second solvation shell water molecule.

The dynamics of the photoinduced reaction producing electronically excited CaF when 1:1 Ca.CH(sub 3)F complexes are deposited at the surface of large argon clusters are examined using the 'cluster isolated chemical reactions' technique. The observations suggest that a profound alteration of the calcium electronic structure and a control of the reaction by the CF stretch in CH(sub 3)F.

The 1(super 2)A', 1(super 2)A', 2(super 2)A', 2(super 2)A', and 3(super 2)A' states of the CH3F(super +) ion are studied. The 1(super 2)A' state is predicted to be the ground state, and the C(sub s)-state energy levels are different from those of the CH3F(super +) ion.

New series of Cu(super II) chemical vapor deposition (CVD) precursors are introduced, where the copper metal is chelated by two fluorinated imino alcoholate or amino alcoholate ligands. It can be noted that the low concentration of O2 promotes partial ligand oxidation, thus releasing the reduced copper on the substrate and affording the high-purity copper deposit.

The preparation and characterization of the first series of platinum(II) complexes with (fluoren-9-ylidene)methanedithiolate and its 2,7-di-tert-butyl- and 2,7-dimethoxy-substituted derivatives and also the effect of the electron-donating character of the dithiolato ligands on their photoluminescence and reactivity are described. The oxidation and protonation reactions of the anionic complex with (2,7-di-tert-butyfluoren-9-ylidene)methanedithiolate, which lead to the formation of an unprecedented Pt(II)-Pt(IV) dithiolato complex or dithioato complexes, respectively, are presented.

The crystal and geometric structure and conformational properties of fluoroformyl trifluoroacetyl (FC(O)SSC(O)CF3) in the gas phase are determined by gas electron diffraction and vibrational spectroscopic methods [IR(gas), IR(matrix), and Raman(liquid)], supplemented by quantum chemical calculations and X-ray diffraction. The crystalline solid consists exclusively of the (sp-sp) conformation and the geometrical parameters agree with those obtained for the molecule in the gas phase.

The role of fluorine in regards to boron diffusion in germanium and silicon preamorphized silicon prior to activation annealing is characterized. Observations reveal that boron atoms can diffuse in germanium-amorphized silicon during recrystallization at elevated temperatures without the assistance of additional dopants.

The charge trapping phenomenon in fluorene-based conjugated polymer poly[9,9-bis(2-ethylexyl)fluorene-2,7-diyl] (PF2/6) and poly[9,9-bis(2-ethylhexyl)fluorene-2,7-diyl] end capped with hole-transporting moieties N, N-bis(4-methylphenyl)-N-phenylamine (PFe/6am 10) is investigated. The thermally stimulated current spectra displays a striking difference with the polarity of load voltage for conjugated polymers, implying an important role of electrodes on the charge-carrier photogeneration in these polymers.

The ubiquity of the fluorine-fluorine bonding interaction for a systematic examination is reported. Teh bond path is shown to persist for a range of internuclear distances (2.3-2.8 angstrom) and a range of relative orientations of the two C-F internuclear axes.

The infrared and ultraviolet-visible absorption cross sections, effective quantum yield of photolysis, and OH, Cl, and NO(sub 3) reaction rate coefficients of CHF(sub 2)CHO are reported. The photolysis of CHF(sub 2)CHO was investigated under pseudonatural tropospheric conditions and an effective quantum yield of photolysis equal to 0.30 plusmn 0.05 over the wavelength range 290-500 nm was extracted.

A study of the dynamics and kinetics of reactions between ions of known recombination energy and CHCl(sub 2)F, CHCIF(sub 2) and CH(sub 2)CIF using the well-established selected ion flow tube (SHIFT) technique is presented. It is concluded that the H(sub 3)O(super +) ion only reacts with CHCl(sub 2)F, even though all of the observed channels are apparently endothermic.

Theoretical investigation on the chemical addition patterns governing the fluorination of single wall carbon nanotubes is presented. Ab initio analysis of the fluorination of small nanotubes concluded that fluorine addition along the nanotube axis direction is favored by a mechanism of carbon framework distortion.

An investigation of the mid-infrared spectra of mixed solutions in liquid xenon containing fluoroform and either ammonia or pyridine is conducted at temperatures between 173 and 213 K. For both Lewis bases, a new band is found in the CH stretching region at a frequency 5 cm(super -1) higher than that of monomer fluoroform, which is assigned to a complex between fluoroform and the Lewis base.

The improved synthetic and isolation procedures are developed that resulted in the preparation of pure C(sub 60)F(sub 20) in sufficient amounts for comprehensive vibrational spectroscopic studies. The results provide a vibrational assignment for the original conjecture of the C(sub 60)F(sub 20) structure with the equatorial belt of 20 fluorine atoms on C(sub 60) cage.

Ab initio electronic structure calculations provide potential energy surfaces for the decomposition of CF(sub 3)CFHO and its competing reaction with O(sub 2). The study indicates that the reaction of CF(sub 3)CFHO with O(sub 2) occurs by means of transition states very similar to those of the reaction of CH(sub 3)CH(sub 2)O with O(sub 2).

Chlorine atom-initiated oxidation of CF(sub 3)CFHCF(sub 2)OCF(sub 3) and CF(sub 3)CFHCF(sub 2)OCF2H gives CF3C(O)F in molar yields. The 100-year time horizon global warming potentials of CF(sub 3)CFHCF(sub 2)OCF(sub 3) and CF(sub 3)CFHCF(sub 2)OCF2H relative to CO2 are 4530 and 4340.

Hydration of KPF6, NaPF6, and LiPF6 is studied in aqueous solutions by means of FTIR spectra of HDO isotopically diluted in H2O. Results shows that the outermost hydration sphere of cations, which is possible to detect with IR spectroscopy, depends on the kind of anion.

The femtosecond fluorescence up-conversion technique is used for analyzing the ultrafast studies of solvation and intramolecular configurational dynamics of large-sized fluorophores in liquid solutions. The application of ultrafast processes can facilitate the in-depth study of the mechanism of molecular relaxation of large-sized molecules.

Fluorine radicals are generated from NF3 or F2 in microwave-generated and low-frequency (LF)-generated plasmas and are passed through flow tubes under various flow, pressure and dilution conditions. The F relative concentration decreases from ~80 percent to ~20 percent, and the F2 relative concentration increases from ~20 percent to ~80 percent, as the pressure is varied over the range 0.5-10 Torr.

A characterization of diamond film electrodes surface-modified by fluorine insertion, through CF4 plasma treatment, is carried out. X-ray photoelectron spectroscopy (XPS) showed that the CF4-plasma treatment results in the formation of a chemical bond between the fluorine and the carbon atoms of the diamond crystals.

A quantitative evaluation of the vigorousness of the contributor or the nakedness of fluoride ion contributors is discussed. The outcome indicates that not much is achieved by enhancing the cation size after a specific level and the less important elements like the chemical and physical aspects override it.

Photoluminescence efficiency of Inp nanocrystals prepared via the dehalosilylation reaction between indium chloride and tris- (trimethylsilyl) phosphine in mixtures of trioctylphosphine and trioctylphosphine oxide can be drastically improved by etching with fluorine compounds. The pure photochemical nature of etching process allowed improving its reproducibility and reliability.

Solution phase mixture synthesis improves efficiency in direct proportion to the number of compounds mixed and has efficiency advantages as well as favorable reaction kinetics. The utility of a fluorous mixture synthesis is demonstrated by the preparation of a 560-membered library of analogues of the natural product mappicine.

Photoluminescence efficiency of Inp nanocrystals prepared via the dehalosilylation reaction between indium chloride and tris- (trimethylsilyl) phosphine in mixtures of trioctylphosphine and trioctylphosphine oxide can be drastically improved by etching with fluorine compounds. The pure photochemical nature of etching process allowed improving its reproducibility and reliability.

A 2-site model of fluoroform (CHF3) is developed for use in simulations of solvation in the near critical regime. The model is optimized to reproduce the critical point and the liquid-vapor coexistence curve of the real fluid.

The reinvestigation of the molecular structure of the parent molecule N(sub 4)P(sub 4)F(sub 8) by using x-ray diffraction, gas electron diffraction and differential scanning calorimetry is described. The results from each of these measurements support a nonplanar eight-membered ring for N(sub 4)P(sub 4)F(sub 8) that is puckered and that undergoes a phase transition at -74 degrees C.

The electronic structure and excitation energies of an M center in LiF crystals are studied employing ab initio computations using an embedded cluster method. The advantages and limitations of the presented computational approach are discussed.

Kohn-Sham solutions are constructed from ab initio densities obtained with multireference configuration interaction (MRCI) calculations for the transition state (TS) and for the intermediate complex (IC) of a prototype symmetrical reaction. The generalized approximations (GGAs) overestimate the relative stability of the systems in the experiment.

Amorphous carbon (a-C) films with low hydrogen content were deposited at low substrate temperatures from a chlorinated hydrocarbon (CH3CL) by photoinduced chemical vapor deposition with a fluorine laser (157 nm). The optical gap, as determined by photothermal deflection spectroscopy (PDS), decreased from 2.3 to 0.1 eV when the substrate temperature was increased from 303 to 643 K.

The method of ozonolysis of unsaturated organotrifluoroborates to the corresponding carbonyl moieties under standard conditions is described. The technique has given oxo-functionalized organotrifluoroborates that cannot be developed directly via either transmetalation or hydroboration protocols.

The pump-probe spectroscopy was used to investigate the primary photoreactions of 3',5'-dimethoxybenzoin (DMB) acetate and fluoride following photoexcitation by a subpicosecond laser flash. The findings reveal that DMB is an excellent protecting group for the investigation of flash processes such as protein folding.

The reactivity of intrazeolite photooxidations can be enhanced by a singlet oxygen friendly environment, where the quenching processes are slowed down and the [super 1][O.sub.2] lifetime is increased. The doping of zeolite with fluoroorganic cation has resulted in an increase in the singlet oxygen lifetime at 12 [micro]s.

A new strategy to construct the six-five-six ring system and an application of the methodology to the total synthesis of (plusmn)-4, with a shorter synthetic route and much-improved overall yield is reported. The methodology is applied to the synthesis of (plusmn)-dichroanal B and allowed to achieve a remarkably shorter synthesis, compared to the previously reported total synthesis.

The key factors affecting the competition between alpha- and beta-elimination channels adsorbed ethyl groups on a meal surface were examined by fluorine substitution. The destabilizing eclipsed interactions and the stabilizing vicinal hyperconjugation contribute significantly to the transition state energitics in the beta-elimination and alpha-elimination respectively by the judicious alteration of the number and position of the fluorine substituents in the ethyl group bound to Cu(I00).

The electron-paramagnetic-resonance method is used to study the fictive temperature (T(sub f)) and fluorine (F)-doping concentration dependences of self-trapped holes (STHs) in silica glasses created by UV irradiation at low temperatures. The results reveal that the change in both T(sub f) and F doping can modify the network of SiO2 glass, leading to the suppression of the formation of STHs.

Heteroleptic copper(II) complexes were synthesized form three different meso-substituted pyridyl- and quinoline-dipyrrinato ligands (3-pyrdpm, 3-quindpm, and 4-quinpdm). It is revealed that flourine-fluorine contacts could be used to modulate supramolecular structures in the solid state.