Helium atom diffraction study of low coverage phases of decanethiol self-assembled monolayers prepared by supersonic molecular beam deposition

► Decanethiol self-assembled monolayers were grown on Au(1 1 1) by using supersonic molecular beam deposition. ► Low coverages striped phases were studied. ► Coverage was determined by monitoring helium specular reflection intensity. ► Different physisorbed states with energies ranging from 0.42 eV to 0.74 eV were observed. ► Two chemisorbed states with energies of 1.30 ± 0.02 eV and 1.45 ± 0.05 eV were observed.