A fundamental understanding of the enantiospecific interactions between chiral adsorbates and understanding of their interactions with chiral surfaces is key to unlocking the origins of enantiospecific surface chemistry. Herein, the adsorption and decomposition of the amino acid proline (Pro) have been studied on the achiral Cu(110) and Cu(111) surfaces and on the chiral Cu(643)
Structure sensitive enantioselectivity on surfaces: tartaric acid on all surfaces vicinal to Cu(111)
Comprehensive mapping of enantiospecific surface reactivity versus the crystallographic orientation of Cu( hkl ) surfaces vicinal to Cu(111) has been conducted using a spherically shaped single crystal on which the surface normal vectors, [ hkl ], span all possible orientations lying with 14° of the [111] direction. This has allowed direct measurement on 169 different Cu( hkl ) surfaces of the two rate constants, k (hkl)i and k (hkl)e, that determine the kinetics of the vacancy-mediated, explosive decomposition of tartaric acid (TA). The initiation rate constant, k (hkl)i, quantifies the kinetics of an initiation step that creates vacancies in the adsorbed TA monolayer. The explosion rate constant, k (hkl)e, quantifies the kinetics of a vacancy-mediated explosion step that results in TA decomposition and product desorption. Enantiospecificity is revealed by the dependence of TA decomposition kinetics on the chirality of the local surface orientation. Diastereomerism is demonstrated by the fact that d -TA is more reactive than l -TA on S surfaces while l -TA is more reactive on R surfaces. The time to reach half coverage, t (hkl)1/2, during isothermal TA decomposition at 433 K allowed determination of the most enantiospecific surface orientation; Cu(754). The ideal Cu(754) surface structure consists of (111) terraces separated by monoatomic steps formed by the (100) and (110) microfacets.
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- Award ID(s):
- 2102082
- NSF-PAR ID:
- 10322864
- Date Published:
- Journal Name:
- Materials Advances
- Volume:
- 3
- Issue:
- 4
- ISSN:
- 2633-5409
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d1ma00876e
