Related Experiment Video
Updated: Jul 20, 2026
09:17
Assembly of Gold Nanorods into Chiral Plasmonic Metamolecules Using DNA Origami Templates
Published on: March 5, 2019
Naphtho[2,3-a]pyrene forms chiral domains on Au111
C Brian France1, B A Parkinson
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, USA.
Journal of the American Chemical Society
|October 16, 2003
Summary
Researchers created chiral domains using naphtho[2,3-a]pyrene (NP) molecules on a gold surface. High-resolution imaging revealed these domains contained only one enantiomer, suggesting potential for chiral molecule separation.
Area of Science:
- Surface science
- Supramolecular chemistry
- Chirality studies
Background:
- Two-dimensional (2D) chiral molecules are crucial for developing advanced materials.
- Controlling enantiomeric self-assembly on surfaces is a key challenge in nanotechnology.
- Understanding molecular interactions on metal surfaces informs catalysis and molecular electronics.
Purpose of the Study:
- To investigate the self-assembly of 2D chiral molecules on a metal surface.
- To determine the enantiomeric composition of the resulting molecular domains.
- To explore the potential applications of these chiral domains in molecular recognition.
Main Methods:
- Preparation of chiral molecular films via ultrahigh vacuum (UHV) evaporation.
- High-resolution scanning tunneling microscopy (STM) for surface imaging.
- Analysis of molecular ordering and domain formation.
Main Results:
- Naphtho[2,3-a]pyrene (NP) molecules formed distinct chiral domains on the Au(111) surface.
- STM observations confirmed the presence of enantiomerically pure domains, not racemic mixtures.
- A structural model consistent with the experimental data was proposed.
Conclusions:
- Achieved enantioselective self-assembly of 2D chiral molecules on a metal surface.
- Identified chiral pockets within the NP domains as potential binding sites for 3D chiral molecules.
- Demonstrated a pathway for creating surfaces with tailored chiral recognition properties.
More Related Videos
Related Concept Videos
02:54Coordination Compounds and Nomenclature
In most main group element compounds, the valence electrons of the isolated atoms combine to form chemical bonds that satisfy the octet rule. For instance, the four valence electrons of carbon overlap with electrons from four hydrogen atoms to form CH4. The one valence electron leaves sodium and adds to the seven valence electrons of chlorine to form the ionic formula unit NaCl (Figure 1a). Transition metals do not normally bond in this fashion. They primarily form coordinate covalent bonds, a...
02:51Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
02:57Coordination Number and Geometry
For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to molecular geometry. The most common structures of the complexes in coordination compounds are octahedral, tetrahedral, and square planar.
02:34Structural Isomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
02:42Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
02:58Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...