References of "Hubin-Franskin, Marie-Jeanne"
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See detailC 1s and N 1s core excitation of aniline: Experiment by electron impact and ab initio calculations
Duflot, D.; Flament, J. P.; Giuliani, Alexandre et al

in Physical Review A (2007), 75(5), 052719

Core shell excitation spectra of aniline at the carbon and nitrogen 1s edges have been obtained by inner-shell electron energy-loss spectroscopy recorded under scattering conditions where electric dipolar ... [more ▼]

Core shell excitation spectra of aniline at the carbon and nitrogen 1s edges have been obtained by inner-shell electron energy-loss spectroscopy recorded under scattering conditions where electric dipolar conditions dominate, with higher resolution than in the previous studies. They are interpreted with the aid of ab initio configuration interaction calculations. The spectrum at the C 1s edge is dominated by an intense pi(*) band. The calculated chemical shift due to the different chemical environment at the carbon 1s edge calculated is in agreement with the experimental observations within a few tenths of an eV. The transition energies of the most intense bands in the C 1s excitation spectrum are discussed at different levels of calculations. In the nitrogen 1s excitation spectrum the most intense bands are due to Rydberg-valence transitions involving the sigma(*)-type molecular orbitals, in agreement with the experiment. This assignment is different from that of extended Huckel molecular orbital calculations. The geometries of the core excited states have been calculated and compared to their equivalent core molecules and benzene. [less ▲]

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See detailThe nonlinear optical, magnetic, and Mossbauer spectral properties of some iron(III) doped silica xerogels
Rebbouh, L.; Rosso, Vanessa ULg; Renotte, Yvon ULg et al

in Journal of Materials Science (2006), 41(10), 2839-2849

Iron(III) species dispersed in silica have been synthesized with a sol-gel process. The iron(III) was introduced as the acetylacetonate complex into a solution of tetraethoxysilane to yield, after ... [more ▼]

Iron(III) species dispersed in silica have been synthesized with a sol-gel process. The iron(III) was introduced as the acetylacetonate complex into a solution of tetraethoxysilane to yield, after evaporative drying, pellets or monoliths. Two gels were dried very slowly over a period of five months in order to prepare a defect free monolith useful for nonlinear optical studies. Z-scan experimental studies on the resulting, transparent, monolithic, doped solid revealed an optical Kerr effect, a third order nonlinear optical phenomenon showing a linear dependence of the refractive index on the irradiance with a nonlinear refractive index, n(2), of -1.95 x 10(-11) cm(2)/W. Magnetic susceptibility studies between 4.2 and 295 K revealed paramagnetic behavior with a Curie constant of 4.433 (emu/mol)K and a Weiss temperature of -7.1 K. Magnetization studies at 5 K and at applied fields of up to 4 T and Mossbauer spectral studies between 4.2 and 295 K revealed a 50:50 mixture of paramagnetic species and nanoparticles with an average particle radius of 1.3 +/- 0.2 nm. A blocking temperature of 70 K and a magnetic anisotropy energy of 2.4 x 10(5) J/m(3) stop are derived from the Mossbauer spectra. (c) 2006 Springer Science + Business Media, Inc. [less ▲]

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See detailA structural, magnetic, and Mossbauer spectral study of several Na-Mn-Fe-bearing alluaudites
Hatert, Frédéric ULg; Long, G. J.; Hautot, D. et al

in Physics and Chemistry of Minerals (2004), 31(8), 487-506

The synthesis and the chemical, structural, magnetic, and Mossbauer spectral characterization of three synthetic alluaudites, Na2Mn2Fe(PO4)(3), NaMn Fe-2(PO4)(3) and (Na2MnFeFeIII)-Fe-II(PO4)(3), and a ... [more ▼]

The synthesis and the chemical, structural, magnetic, and Mossbauer spectral characterization of three synthetic alluaudites, Na2Mn2Fe(PO4)(3), NaMn Fe-2(PO4)(3) and (Na2MnFeFeIII)-Fe-II(PO4)(3), and a natural sample with the nominal composition of NaMn Fe-2(PO4)(3), collected in the Buranga pegmatite, Rwanda, are reported. All four compounds have the expected alluaudite monoclinic C2/c structure with the general formula [A(2)A(2)'][A(1)A(1)'A(1)(2)'']M(1)M(2)(2)(PO4)(3) in which manganese(II) is on the M(1) site and manganese(II), iron(III) and, in some cases, iron(II) on the M(2) site. The X-ray structure of Na2Mn2Fe(PO4)(3) also indicates a partially disordered distribution of Na-I and Mn-II on the M(1) and A(1) crystallographic sites. All four compounds are paramagnetic above 40 K and antiferromagnetically ordered below. Above 40 K the effective magnetic moments of NaMnFe2(PO4)(3) and Na2MnFeII Fe-III(PO4)(3) are those expected of high-spin manganese(II) and iron(III) with the (6)A(1g) electronic ground state and high-spin iron(II) with the T-5(2g) electronic ground state. In contrast, the effective magnetic moment of Na2Mn2Fe(PO4)(3) is lower than expected as a result of enhanced antiferromagnetic exchange coupling by the manganese(II) on the M(2) site. The Mossbauer spectra of all four compounds have been measured from 4.2 to 295 K and have been found to be magnetically ordered below 40 K for Na2Mn2Fe(PO4)(3) and similar to35 K for the remaining compounds. The Mossbauer spectra of Na2Mn2Fe(PO4)(3) exhibit the two expected iron(III) quadrupole doublets and/or magnetic sextets expected for a random distribution of manganese(II) and iron(III) ions on the M(2) site. Further, the Mossbauer spectra of (Na2MnFeFeIII)-Fe-II(PO4)(3) exhibit the two iron(II) and two iron(III) quadrupole doublets and/or magnetic sextets expected for a random distribution of iron(II) and iron(III) on the M(2) site. Surprisingly, the synthetic and natural samples of NaMnFe2(PO4)(3) have 19 and 10% of iron(II) on the M(2) site; apparently the presence of some iron(II) stabilizes the alluaudite structure through the reduction of iron(III)-iron(III) repulsion. The temperature dependence of the iron(II) quadrupole splitting yields a 440 to 600 cm(-1) low-symmetry component to the octahedral crystal field splitting at the M(2) site. The iron(II) and iron(III) hyperfine fields observed at 4.2 K are consistent with the presence of antiferromagnetic ordering at low temperatures in all four compounds. [less ▲]

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See detailThe electronic states of 2-furanmethanol (furfuryl alcohol) studied by photon absorption and electron impact spectroscopies
Giuliani, A.; Walker, I. C.; Delwiche, Jacques ULg et al

in Journal of Chemical Physics (2003), 119(14), 7282-7288

The photoelectron spectrum of 2-furanmethanol (furfuryl alcohol) has been measured for ionization energies between 8 and 11.2 eV and the first three ionization bands assigned to pi(3), pi(2), and n(o ... [more ▼]

The photoelectron spectrum of 2-furanmethanol (furfuryl alcohol) has been measured for ionization energies between 8 and 11.2 eV and the first three ionization bands assigned to pi(3), pi(2), and n(o) ionizations in order of increasing binding energy. The photoabsorption spectrum has been recorded in the gas phase using both a synchrotron radiation source (5-9.91 eV, 248-125 nm) and electron energy-loss spectroscopy under electric-dipole conditions (5-10.9 eV, 248-90 nm). The (UV) absorption spectrum has also been recorded in solution (4.2-6.36 eV, 292-195 nm). The electronic excitation spectrum appears to be dominated by transitions between pi and pi* orbitals in the aromatic ring, leading to the conclusion that the frontier molecular orbitals of furan are affected only slightly on replacement of a H atom by the -CH2OH group. Additional experiments investigating electron impact at near-threshold energies have revealed two low-lying triplet states and at least one electron/molecule shape resonance. Dissociative electron attachment also shows to be widespread in furfuryl alcohol. (C) 2003 American Institute of Physics. [less ▲]

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See detailA Magnetic and Mössbauer Spectral Study of Several Na-Mn-Fe-bearing Alluaudites
Long, Gary J.; Hautot, Dimitri; Hatert, Frédéric ULg et al

Poster (2001)

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See detailElectronic Autoionization in Carbon monoxide: The effects of the Vibrational Motion.
Leyh, Bernard ULg; Delwiche, Jacques ULg; Hubin-Franskin, Marie-Jeanne ULg et al

in Chemical Physics (1987), 115

New continuous measurements of the vibrationally resolved photoionization cross sections of CO+ X2Sigma+ and A2Pi between 63 and 83 nm are reported. We assign the Rydberg series converging to CO+ A2Pi ... [more ▼]

New continuous measurements of the vibrationally resolved photoionization cross sections of CO+ X2Sigma+ and A2Pi between 63 and 83 nm are reported. We assign the Rydberg series converging to CO+ A2Pi. The effects of the vibrational motion are interpreted on the basis of the Condon approximation. This approximation is shown to allow a qualitative understanding of the decay of the Rydberg series converging to the A2Pi and B2Sigma+ states of CO+. [less ▲]

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See detailMeasured and Calculated Partial Photoionization Cross Sections of CO between 15 and 40 eV.
Leyh, Bernard ULg; Raseev, G.; Hubin-Franskin, Marie-Jeanne ULg et al

in Lahmani, F.; Castex, M. C.; Collin, Jacques (Eds.) et al Photophysics and Photochemistry above 6 eV. (1985)

Vibrationally resolved partial photoionization cross sections of CO have been measured and theoretical partial cross sections have been calculated using the method of Raseev et al. and the two-step MQDT ... [more ▼]

Vibrationally resolved partial photoionization cross sections of CO have been measured and theoretical partial cross sections have been calculated using the method of Raseev et al. and the two-step MQDT formulation of Giusti-Suzor and Lefebvre-Brion. We discuss the physical nature of the shape resonances appearing in the epsilon-sigma continua and we analyze their vibrational selectivity. A new assignment of the Rydberg series converging to CO+(B2Sigma+) is suggested and their electronic and vibrational selectivity is discussed. [less ▲]

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See detailIntramolecular dynamics by photoelectron spectroscopy. II. Nonadiabatic processes.
Dehareng, Dominique ULg; Leyh, Bernard ULg; Desouter-Lecomte, Michèle ULg et al

in Journal of Chemical Physics (1983), 79(8), 3719-3724

The Fourier transform of an electronic spectrum leads to an autocorrelation function which provides information on the propagation of the wave packet on the potential energy surface of the electronic ... [more ▼]

The Fourier transform of an electronic spectrum leads to an autocorrelation function which provides information on the propagation of the wave packet on the potential energy surface of the electronic state reached in the transition. The formula is valid even when nonadiabatic interaction is present, i.e., when the wave packet splits at a particular surface crossing with one part branching off to another potential energy surface. An explicit expression of the correlation function is given for a model of several discrete states interacting with a continuum. Closed-form solutions are given in the case of one and two resonances. A very simple formula valid in the strong coupling limit is also derived. The method is applied to the photoelectron spectrum of state A 2Sigma+ of HBr+, which is shown to correspond to the strong couplig case. [less ▲]

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See detailDissociative Ionization of Carbon Disulphide in the Gas Phase. Heat of Formation of the CS Radical.
Hubin-Franskin, Marie-Jeanne ULg; Locht, Robert ULg; Katihabwa, J.

in Chemical Physics Letters (1976), 37(3), 488-493

Measurements of the appearance potentials and the kinetic energies of S+ and CS+ ions formed by electron impact on carbon disulphide in the gas phase lead us to propose a value as low as 34+/-6 kcal/mole ... [more ▼]

Measurements of the appearance potentials and the kinetic energies of S+ and CS+ ions formed by electron impact on carbon disulphide in the gas phase lead us to propose a value as low as 34+/-6 kcal/mole for the heat of formation of the CS radical in its ground electronic state. It is also shown that the predissociation of the A2Piu or X2Pig and the B2Sigmau/+ molecular ion states by a repulsive 4Sigma- state giving rise to S+ ions, observed through metastastable ions study, occur at 13.45 eV and 14.55 eV respectively. [less ▲]

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