From local adsorption stresses to chiral surfaces: (R,R)-tartaric acid on Ni(110)

Vincent Humblot, Sam Haq, Chris Muryn, Werner A. Hofer, Rasmita Raval

    Research output: Contribution to journalArticlepeer-review


    The chiral molecule (R,R)-tartaric acid adsorbed on nickel surfaces creates highly enantioselective heterogeneous catalysts, but the nature of chiral modification remains unknown. Here, we report on the behavior of this chiral molecule with a defined Ni(110) surface. A combination of reflection absorption infrared spectroscopy, scanning tunneling microscopy, and periodic density functional theory calculations reveals a new mode of chiral induction. At room temperatures and low coverages, (R,R)-tartaric acid is adsorbed in its bitartrate form with two-point bonding to the surface via both carboxylate groups. The molecule is preferentially located above the 4-fold hollow site with each carboxylate functionality adsorbed at the short bridge site via O atoms placed above adjacent Ni atoms. However, repulsive interactions between the chiral OH groups of the molecule and the metal atoms lead to severely strained adsorption on the bulktruncation Ni(110) surface. As a result, the most stable adsorption structure is one in which this adsorption-induced stress is alleviated by significant relaxation of surface metal atoms so that a long distance of 7.47 Å between pairs of Ni atoms can be accommodated at the surface. Interestingly, this leads the bonding Ni atoms to describe a chiral footprint at the surface for which all local mirror symmetry planes are destroyed. Calculations show only one chiral footprint to be favored by the (R,R)-tartaric acid, with the mirror adsorption site being unstable by 6 kJ mol-1. This energy difference is sufficient to enable the same local chiral reconstruction and motif to be sustained over 90% of the system, leading to an overall highly chiral metal surface.

    Original languageEnglish
    Pages (from-to)503-510
    Number of pages8
    JournalJournal of the American Chemical Society
    Issue number3
    Publication statusPublished - 23 Jan 2002


    Dive into the research topics of 'From local adsorption stresses to chiral surfaces: (R,R)-tartaric acid on Ni(110)'. Together they form a unique fingerprint.

    Cite this