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Conventional solid state synthesis is based on reacting
solids which, even after intense milling, are dispersed on a
macroscopic scale compared to atomic distances. As a
consequence, solid state reactions require a high thermal
activation, favoring the formation of thermodynamically
stable products. One option for straight forwardly
overcoming these complications is to reduce the transport
distances to atomic dimensions. This idee is realized with
our new synthesis method ´Low-Temperature - Atomic Beam
Deposition` (LT-ABD), which allow to disperse the components
of the desired product at an atomic level and in an
appropriate ratio. Such randomly 'frozen' mixtures of
atoms could serve as an ideal starting point for solid state
syntheses from atoms.
The samples are in-situ investigated by an adequate X-ray
diffractometer as a function of temperature. For synthesis,
several UHV-preparation chambers are available with a special
cart-system, which allows sample transfer maintaining vacuum
and cooling. The synthesis method is closely connected to the
theoretical work in the department, in particular with the
global exploration of the energy landscape
of chemical systems, to realize the predicted (meta)stable compounds
experimentally.
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