Discovery of a tilted form of benzene chemisorbed on Pd(111): As NEXAFS and photoemission investigation

The chemisorption geometry within a dense benzene overlayer on Pd(111) has been investigated by a combination of NEXAFS, UPS and XPS. It is demonstrated that the molecule can adopt a tilted configuration with the molecular plane inclined at 30 ° to the metal surface. This finding provides a highly satisfactory explanation for the unexpectedly high efficiency of low-temperature acetylene → benzene conversion on Pd(111).