Variable pressure soft X-Ray Absorption
A variable pressure soft X-ray Absorption (vP-XAS) experiment has been constructed by FHI that works in the conversion electron yield detection mode.
This set-up allows to measure surface sensitive X-ray absorption spectra in a pressure range between 102 – 105 Pa, i.e. up to atmospheric pressure, at temperatures up to 400°C. This instrument makes it feasible to study heterogeneous catalytic reactions in a broad pressure range and hence allows to link results obtained with AP-XPS and measurements done in a catalytic reactor.
A sketch of the setup is shown in Fig. 1. Similar to the AP-XPS, the vP-XAS setup is rigged in a movable frame which provides the possibility to exchange both machines to be used as endstation at EMIL.