Self-assembled line growth of allyl alcohol on the H-terminated Si(100)-(2 × 1) surface

Using first-principles density-functional calculations, we investigate the growth mechanism of allyl alcohol (ALA) line on the H-terminated Si(100)-(2 × 1) surface. Unlike the allyl mercaptan (CH2 = CH − CH2 − SH) line, which was observed to grow across the Si dimer rows, we find that ALA (CH2 = CH − CH2 − OH) has the line growth along the Si dimer row. The self-assembled growth of ALA line occurs via the radical chain reaction mechanism, similar to the case of a typical alkene molecule, styrene. Our calculated energy profile along the reaction pathway shows that the different growth direction of ALA line compared with that of allyl mercaptan line is ascribed to the great instability of the oxygen radical intermediate, which prevents the line growth across the dimer rows.