Instrumentation
Solid-liquid diffraction cell
It has been designed and built a cell for the study of solid-liquid interfaces. It can be mounted on the 6-circle diffractometer, allowing the diffraction study of a sample in contact with a liquid. The cell has different capabilities:
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A thermostatic bath for controlling the temperature.
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Connections to modify the liquid composition and a magnetic stirring system.
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Possibility to introduce electrodes.
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Motorized system for sample positioning inside the liquid.
This design allows the temperature and composition control of the liquid in situ. It is also possible to modify the thickness of the liquid layer over the sample. The use of electrodes permits the realization of electrochemical experiments.
High Energy Electron analyzer
High Energy-XPS will allow the study of buried interfaces in a non-destructive way. One of the important limitations nowadays is the energy range of the existing analyzers. In the SpLine, a new analyzer that will be able to measure electrons with an energy up to 15 keV with an outstanding resolution. The analyzer is coupled to a UHV chamber and a diffractometer, and it will be possible to perform simultaneously HEXPS and diffraction experiments.
Optical elements
- Double crystal monochromator (DLC): pseudo channel-cut type with two Si(111) crystals in the (-n,+n) configuration moved together by a simple goniometer circle. The exit height of the beam is fixed and it is provided by a unique parallel translation of the second crystal with respect to the first one. The sagital dynamical focusing at the different sample positions is achieved by a novel bender that curves a multi-rips thin Si(111) crystal (ESRF-model). The curvature radius can be varied in the 0.9-22 m range. The bender consists of a monolithic link mechanism with six notch flexure hinges and it is activated pneumatically. The bender is mounted on two perpendicular actuating monolithic notch flexure hinges, for pitch and roll adjustments. An additional rotation (yaw) and translation are also included. The first crystal is water cooled.
- Mirrors: all the mirrors have silicon substrates and 1.5 m length. The 1st mirror of the A-branch has two stripes of Rh and Si and collimates the white beam. The 1st mirror of the B-Branch is flat and Rh-coated. The 2nd mirrors of branches A and B have two Rh and Si coated stripes and focus the bean meridionally. The pre-monochromator mirrors are water-cooled. Primary and secondary slits: water-cooled (primary slits) and remotely controlled. They allow the setting of the vertical and horizontal apertures in the *** range with 1** micron precision. Safety shutter: water cooled.
- Attenuattors: there are three attenuators in total. Each one has four filters, allowing a total of 64 different combinations.
- Be-Valves: they can be removed when working at low energies to minimize absorption.