COMBINED ELEVATED PRESSURE REACTOR AND ULTRAHIGH-VACUUM SURFACE-ANALYSIS SYSTEM

A combined elevated pressure reactor/ultrahigh vacuum (UHV) surface an alytical system has been designed for studies of heterogeneous catalyt ic reactions. The reaction cell is separated from the surface analysis chamber by a differentially pumped sliding seal. This feature allows simple in situ sample transfer capabilities from the surface analysis region to the reactor cell and also facilitates the introduction and r epair of the sample and/or holder with no significant perturbation of the UHV analysis chamber vacuum. The pumping arrangements provide for rapid evacuation of the reaction cell as well as maximum sensitivity w ith respect to the detection of reaction products.