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The effect of aromatic swelling agents on the pore geometry and pore size of mesoporous M41S materials is investigated, where benzene and 1,3,5-trisubstituted aromatic compounds are used as swelling agents. Benzene is incorporated and immobilized close to the surface of the micelle, whereas the more hydrophobic trisubstituted aromatic compounds are located in the hydrophobic core of the micelle, where they retain some mobility.

Experimental evidence for a strong polar ordering induced by wire poling under high electric field conditions in the amorphous pDR1M azobenzene polymer is reported. A comparative study of the electronic spectra of a DR1 solution in chloroform and of an unpoled, a poled and a thermally depoled film is discussed.

The ab initio maximization and electrostatic potentials are calculated for numerous disubstituted benzenes. A considerable six parameter correlation between logP and the calculated descriptors for a training set of representative disubstituted benzenes is presented.

The aromaticity of benzenes annelated to small rings is examined using ab initio molecular orbital calculations. The aromaticity of benzene is explained in terms of the similar electronic states for six pi bonds from the configuration interplay localized molecular orbital CASSCF analysis on the basis of ab initio measurements.

The thin films of a benzylic amide macrocycle, the common component of a wide class of mechanically interlocked molecules, are prepared by vapor deposition on Au(111). The films are characterized by monochromated X-ray photoelectron spectroscopy (XPS) and high resolution electron energy loss spectroscopy (HREELS).

The electronic structure of benzene adsorbed on single-domain Ge(100-(2*1) and on a single-domain Ge monolayer grown on SDi(100)-(2*1) is investigated by angle-resolved ultraviolet photoemission spectroscopy (ARUPS). The weekly bound benzene species can only be observed on Ge(100) but not on Si(100) or Ge/Si(100) and the reason for this bonding is because it is based on kinetic hindrance of saturation of the chemisorbed species.

The CAS MCSCF/CAS MCQDPT2 ab initio method utilizing the 6-31G* basis set was used to study the 1,4-cycloaddition reactions of singlet oxygen with s-cis-1,3-butadiene to form 3,6-dihydrol[1,2]dioxin and to benzene to form 2,3-dioxabicyclo-[2.2.2]octa-5,7-diene.

Research is presented describing the study of cycloalkane solvent holes to determine reversible reactions.

Issues concerning the use of molecular dynamics simulations to calculate the relative hydration free energies of organic molecules are presented.

This research focuses on a comparison of the electronic properties, vibrational frequencies, binding energies, and the geometries of the minimal energy conformers of the C6H6-AlX3 and the corresponding C2H4-AlX3 systems.

A generalized approach to refractive indices calculation with quantum mechanical models has been discussed. Results indicate that refractive indices for benzene in the gas and liquid phase agree with the limited experimental data.

Temperature dependent rate constants and product branching fractions have been used for the reactions of atmospheric plasma cations with benzene. A schematic reaction coordinate diagram of the primary dissociation channels of C (sub)6 H (sub)6 (super)+ is presented.

An UV-vis and FTIR study of the interactions of betacarboline with benzene, naphthalene and phenanthrene has been carried out. The authors suggest stabilization of the complexes by the hydrogen-bonding interaction between NH betacarboline group and the pi-delocalized benzenoid substrate electrons.

The experimental and theoretical studies of the ring-chain tautomerism (H-atom transfer and cyclization) for 2-acetylbenzonic acid at both ground and electronically first excited states are presented. (super 1)H and (super 13)C NMR studies in solution confirm the existence of equilibrium between the open and ring structures at the ground state, with the ring one being dominant (~90%).

The bonding pattern in the tridehydrobenzenes isomers (1,2,3-, 1,2,4-, 1,3,5- C6H3) are studied by electronic structure calculations. The energetic, strength, stabilization and structure pf the partial bonds formed by unpaired electrons between the radical center are reported.

A full set of 34 empirically determined harmonic force constants F (sub i, k) for benzene in symmetries co-ordinates is investigated. The study can lead to refinement of the empirically determined harmonic force through a better fit of calculated and experimentally measured vibrational energy levels.

O2 Delta(sub g) (super 1)-TEMPCO system n benzene by means of TR-ESR was used to observe the net Abs CIDEP on TEMPO. Measurements of P delta values are studied to build a new O2 Delta(sub g) (super 1) detection system.

Using the CASSCF calculation for the excited state relaxed surface scans along CNN bending (inversion), the CNNC torsion (rotation) and the concerted CNN bending (concerted inversion) reaction pathways, the photoisomerization mechanism of azobenzene together with the rotation inversion controversy is examined. The possibility of the occurrence of an efficient electronic relaxation between the two electronic states is remote as the energy gap is too large.

HM-IE was tested for interaction energies of Ne2, (C2H2)(sub 2), and N2-benzene for many orientations sampling the entire potential energy surface. It was found to be in excellent agreement with the CCSD(T)LBS results while requiring considerably less computational time and resources.

Density functional theory is used to study the geometries, electronic structures, harmonic vibrational frequencies, and high-energy density material properties of 1,3,4,6,7,9,9b-heptaazaphenalene and its ten derivatives at the B3LYP/aug-cc-pVDZ level of theory. Geometry studies show that all of the compounds have a highly symmetric structure with a planar and rigid heteroring.

The photophysical and photochemical properties of some aza-analogues of 1,4-distyrylbenzene, bearing a nitrogen heteroatom in the side arene rings are investigated. By selective photoexcitation, information about the conformational equilibria of the compounds bearing side quinolyl groups or the pyridyl central ring, due to internal rotation around the quasi single bonds with the ethenic carbons was obtained.

A spectroscopy study of the van der Waals complex between benzene and hexafluorobenzene formed in liquid krypton solutions is reported. It is suggested that the interaction energy of arenes with fluorinated arenes in solution is substantially smaller than that of a typical hydrogen bond and would not be expected to result in persistent structural features in solution.

Two-dimensional (2D) molecular films composed of mixtures of an amphiphilic polymer containing an azobenzene (Az) side chain and a nematic liquid crystal molecule, is prepared on both water surface and solid substrate at various molar ratios. The results show the versatility and validity of the 2D system for observation and understanding of the phase separation behavior and its photoresponse.

A variety of rotational-level population distributions are prepared in the 6(super 1) vibrational level of (super 1)B(sub 2u) benzene, and the rotational distributions within 0 degree that result from collisions with H2, D2, or CH4 are observed. The 0 degree distributions for D2 are broader than for H2, illustrating that the reduced mass and rotational-level spacings play an important role in determining the rotational changes that occur.

The isotopmer selected N = 2 CH chromophore absorption of (super 12)C(sub 6)H(sub 6) and (super 13)C(super 12)C(sub 5)H(sub 6) near 6000 cm(super -1) at natural abundance are recorded. The (super 12)C(sub 6)H(sub 6) spectrum is compatible with a proposed model of intramolecular vibrational redistribution with a distinct hierarchy of time scales.

Rotationally resolved fluorescence excitation spectra of the N2 van der Waals complex of p-difluorobenzene (pDFB-N2) are recorded in the collision free environment. The data obtained provide information about the structure and internal motion of pDFB-N2 in its ground (S0) and excited (S1) electronic states.

Rotationally resolved fluorescence excitation spectra of the N2 van der Waals complex of p-difluorobenzene (pDFB-N2) are recorded in the collision free environment. The data obtained provide information about the structure and internal motion of pDFB-N2 in its ground (S0) and excited (S1) electronic states.

The vibronic spectroscopy of ortho-, meta-, and para-diethynylbenzene (oDEB, mDEB, and pDEB) were studied by two-color resonant two-photon ionization (R2PI). In all three isomers, the acetylenic C-H stretch fundamental was unshifted from the ground state and no Fermi resonance was seen.

Vibrational energy transfer from the 6(super 1) level of S1((super 1)B(sub 2u)) benzene was studied at low collision energies in supersonic free jet expansions with 11 polyatomic collision partners. The observation that a reasonable amount of energy is transferred into benzene rotation suggests that it is the low-frequency modes of the collision partner that are excited.

The solvent dependence of absorption and fluorescence spectra, fluorescence lifetimes, and quantum yields of various 3-substituted benzanthrone derivatives were investigated. The rate constant and efficiency of intersystem crossing between fluorescent excited state and upper triplet state were strongly influenced by the substituent and by the solvent polarity.

The cation and anion products of the reactions between lead clusters produced in the laser ablation and the benzene molecules seeded in argon are studied by high-resolution reflectron time-of-flight mass spectrometer (RTOFMS). Two conspicuously different and independent reaction mechanisms for lead cluster cations and anions are proposed.

Ab initio and density functional calculations are used to study the structures and thermochemical properties of the benzene-OH adduct (hydroxycyclohexadienyl, CHD-OH). The rate constant for CHD-OH adduct dissociation to C6H6 + OH are calculated and compared to literature data.

The deformation of the carbon skeleton of the benzene ring under substituent impact is analyzed from the structures of 74 monosubstituted derivatives, as determined by ab initio MO calculations. The geometry of the substituted ring is shown to possess valuable information on the electronegativity, resonance, and steric effects of the substituent.

The uptake by 1-octanol of gas-phase alpha-pinene, gamma-terpinene, p-cymene, and 2-methyl-2-hexanol are measured as a function of relative humidity and temperature (263-293 K) with the use of droplet train apparatus. Uptakes of the gas-phase species benzene, H2O, SO2, and H2S are also studied.

The intramolecular vibrational energy redistribution (IVR) and the intermolecular vibrational energy transfer (VET) of selectively excited aromatic molecules in solution (CF2CICFCI2) are observed by femtosecond IR-pump-UV-probe spectroscopy. A characteristic variation of the relaxation dynamics of the aromatic systems upon chemical substitution is observed.

The dehydrogenation of benzene on Pt/ZnO(0001)-O model catalysts was studied with temperature-programmed desorption (TPD) and low-energy ion scattering spectroscopy (LEIS). The LEIS signal suggests that approximately one-third of the adsorbed c-C6D6 on the Pt islands also desorbs molecularly at ~300-480 K.

The calculations on free base tetraphenylporphyrin (H2TPP) in benzene solution using fluorescence up-conversion and transient absorption are presented. A model for explaining the primary intramolecular processes in the Soret, Qy and Qx electronic complexes with specific sequence of time scales and couplings is described.

The threshold photoelectron-photoion coincidence spectroscopy is used to analyze the dissociation dynamics of the bis(benzene) chromium ion, (C6H6)(sub 2)Cr(super +). The two benzene loss reactions are found to be metastable at photon energies near the dissociation boundaries of the precursor ions.

The mono and bis-adducts of benzene of the kind M(C6H6)(sub 1,2)(super +) are obtained in the gas state with first, second and third row transition metal cations and their sensitivities toward molecular oxygen are studied. It is observed that the molecular oxygen activation by early transition metal cations is conserved in the presence of one benzene molecule but ceases in presence of two molecules.

The lambda-dynamics approach to free energy simulations applied the host-guest system of beta-cyclodextrin interacting with a series of monosubstituted benzenes. The study shows that an excellent correlation is obtained between the free energies derived from lambda-dynamics and free energy perturbation results.

The geometries and bonding energies were calculated at B3LYP/3-21G AND B3LYP/DZVP2 levels in a series of [M(eta6-C6H6)](Super n+) where M = Ti, V, Cr, Fe, Co, Ni, and Cu. A correlation between the total benzene charge and the frequency shift of the E1 ring vibration was evidenced that allowed interpretation of experimental data.

The proton NMR and molecular surface area calculations are used to investigate the complex formation of benzenesulfonate (BS) and alpha-cyclodextrin (alpha-CD). In addition, the crystal structure of the complex of sodium benzenesulfonate (BS) and alpha-CD are determined using the Johnson-Bovey theory and the ROESY spectrum.

The energetics and dynamics of benzene in the channels are understood by calculating static potential energy across different cross sections of channels, distribution functions along and across the channel, diffusion coefficients, and reorientational correlation functions. Population of benzene dynamics within the one-dimensional channel is dependent on the channel diameter as well as the modulation of the diameter along the channel and the structural inhomogeneity of the channel wall.

The reorientational motion of benzene is examined in the neat liquid and in a polystyrene/benzene solution, which was, investigated by NMR relaxation as well as MD simulation methods. It is concluded that the rotations about the C(sub 6) axis were much faster than about axis perpendicular to the C (sub 6) axis and this finding is in accordance to a previous MD study by Muller-Plathe.

Research into weak solid-state interactions focuses on a system of 1:1 host-guest compounds of p-tert-butylcalix[4]arene. It is shown that the pyridine nitrogen is located in the calixarene cavity.

Research is presented concerning the use of theoretical simulations to investigate the diffusion and adsorption of benzene in a solution of zeolite HY by use of the density functional theory, molecular mechanics and neutron diffraction, spectroscopy and gravimetry.

The performance of scaling factors for predicting frequencies of the ring modes in several benzene derivatives is determined.