By　means　of　cluster　models　coupled　with　density　functional　theory,　we　have　studied　the　hydroboration　of　the　Ge(1　0　0)-2　×　1　surface　with　BH　3　.　It　was　found　that　the　Ge(1　0　0)　surface　exhibits　rather　different　surface　reactivity　toward　the　dissociative　adsorption　of　BH　3　compared　to　the　C(1　0　0)　and　Si(1　0　0)　surfaces.　The　strong　interaction　still　exists　between　the　as-formed　BH　2　and　H　adspeices　although　the　dissociative　adsorption　of　BH　3　on　the　Ge(1　0　0)　surface　occurs　readily,　which　is　in　distinct　contrast　to　that　on　the　C(1　0　0)　and　Si(1　0　0)　surfaces.　This　can　be　understood　by　the　electrophilic　nature　of　the　down　Ge　atom,　which　makes　it　unfavourable　to　form　a　Ge{single　bond}H　bond　with　the　dissociating　proton-like　hydrogen.　Alternatively,　it　can　be　attributed　to　the　weak　proton　affinity　of　the　Ge(1　0　0)　surface.　Nevertheless,　the　overall　dissociative　adsorption　of　BH　3　on　group　IV　semiconductor　surfaces　is　favourable　both　thermodynamically　and　kinetically,　suggesting　the　interesting　analogy　and　similar　diversity　chemistry　of　solid　surface　in　the　same　group.　©　2005　Elsevier　B.V.　All　rights　reserved.