Deuterium atoms can be absorbed into a palladium (Pd) lattice. They are effectively solidified as an ultrahigh density deuterium lump (Pycnodeuterium) inside each octahedral space within the unit cell of the palladium host lattice. It was once reported that deuterium absorbed into palladium enabled nuclear cold fusion. However, cold fusion by this mechanism has not been generally accepted by the scientific community.
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