Nucleation and growth of a H-induced reconstruction of Ni(110)

The dynamics of the hydrogen-induced reconstruction of Ni(110) at room temperature has been studied by scanning tunneling microscopy. The nucleation and growth of the ``streaky'' (1×{}2) H phase reveal that the reconstruction is very local in nature and evolves as a combined added and missing-row model with -Ni-H- chains growing preferentially along the [11{}0] direction. The hydrogen chemisorption induces a substantial mass transport, which explains why the restructuring is an activated process.