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An automatic θ-θ diffractometer has been built in which X-ray source and detector rotate about a fixed horizontal specimen, in such way that measurements can be carried at equally spaced values of the scattering vector modulus. This especially designed diffractometer for the study of liquids and glassy materials, is provided with a cryostat allowing diffraction measurements down to very low temperatures. Some results are reported concerning liquid gallium at 323 and 203 K., On a réalisé un diffractomètre automatique θ-θ où tube à rayons X et compteur se déplacent autour d'un échantillon fixe, horizontal, de façon à faire des mesures sensiblement équiréparties dans l'espace réciproque. Ce diffractomètre, particulièrement adapté à l'étude des liquides et des substances vitrifiables, a été équipé d'un cryostat qui permet d'effectuer des mesures de diffraction jusqu'à très basse température. Quelques résultats concernant le gallium liquide à 323 et 203 K sont donnés., Bizid Abdelmalek, Bosio Louis, Cortès Robert, Defrain André. Diffractomètre θ-θ à axe horizontal pour étude aux rayons X jusqu'à très basse température. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 100, 1, 1977. pp. 9-14.

A simple spectrometer using a conventional X-ray generator has been constructed for ReflEXAFS measurements at glancing angle. The X-ray source is a sealed X-ray tube with a parabolic mirror. A monochromator with two flat LiF crystals is used. The energy resolution amounts to 8.5 eV at 8 keV. A proportional counter monitors the incident X-ray intensity and a NaI scintillation detector measures the intensity of the reflected beam. This system is free from fluctuations of the incident X-ray intensity and harmonics can be rejected with the energy discrimination. The range of energy is 7 to 18 keV. The ReflEXAFS spectra related to the surface of a nickel sample and a thermally oxided nickel sample are presented.

After a survey of the in-situ techniques used to probe the structure of electrochemical interfaces, we present new results obtained by specular X-ray reflectivity on the liquid-vapor, the liquid-gas and, for the first time, the liquid-water and liquid-electrolyte interface of mercury.

We built a special Langmuir through allowing the use of X-ray reflectivity. Using the device we studied for the first time the density profile of a Langmuir monolayer directly on water. This experiment opens new prospects in particular to measure the roughness of solid films on water subphase.

An attempt is made to compare the structures deduced from X-ray measurements on some pure metals, both in the liquid and the non crystalline state. With Ga and Bi, the liquid and the amorphous solid structures show some similarities and seem to be correlated with the solid phase which occurs when crystallisation takes place. Different behaviour is found with Hg : the liquid structure factor differs from the structure factor in the amorphous state whose main peak is symmetric in form.

An apparatus for X-ray reflection measurements is described. The goniometer is designed for studies on liquid and solid surfaces at grazing angles in the range 0-100 mrad. Typical examples using this set up are reported On decrit un dispositif permettant de tester des modeles de profils de densite au voisinage d'une interface solide (ou liquide)-vapeur. Le principe de la methode consiste a mesurer, en fonction de l'angle d'attaque (de l'ordre de quelques mrad), l'intensite reflechie speculairement par une surface plane lorsque celle-ci recoit un faisceau de rayons X. On donne quelques exemples d'application

Blanconnier Pierre, Bosio Louis, Defrain André, Rimsky Alexandre, Curien Hubert. Étude cristallographique d'une nouvelle forme métastable du gallium : le gallium γ. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 88, 1, 1965. pp. 145-146.