in-situ TEM DF of Pd-H hydrogen absorption
In-situ TEM dark field of 50-200 nm sized Pd-H particles at 0.8 bar pressure. Upon a temperature decrease hydrogen is absorped into the Pd-H lattice and a transformation occurs to a phase with a higher lattice parameter (expansion). Thus diffracted electron beams from particle 1 and 2 enter the objective aperture and the particles light up, especially particle 1. In reverse: at the end of the movie T is increased and the hydrogen quickly leaves particles 1 and 2, the lattices shrink and the particles darken. For more details, see the paper in press in Ultramicroscopy, http://www.sciencedirect.com/science/article/pii/S0304399111002555
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