The properties of crystalline solids can to a large extent be derived from the scale and dimensionality of periodic arrays of coupled quantum systems such as atoms and molecules. Periodic quantum confinement in two dimensions has been elusive on surfaces, mainly because of the challenge to produce regular nanopatterned structures that can trap electronic states. We report that the two-dimensional free electron gas of the Cu(111) surface state can be trapped within the pores of an organic nanoporous network, which can be regarded as a regular array of quantum dots. Moreover, a shallow dispersive electronic band structure is formed, which is indicative of electronic coupling between neighboring pore states.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1126/science.1175141 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
One-Pot Transition-Metal-Free Synthesis of π-Extended Bipolar Polyaromatic Hydrocarbons.
Angew Chem Int Ed Engl
January 2025
Instytut Chemii Organicznej PAN: Instytut Chemii Organicznej Polskiej Akademii Nauk, Institute of Organic Chemistry, Kasprzaka 44/52, 01-224, Warsaw, POLAND.
The development of straightforward synthetic methods for photoactive polycyclic aromatic hydrocarbons (PAHs) that avoid Pd-catalyzed or radical-based processes remains a challenge. Such methods are essential to reducing the cost and environmental impact of organic photodevices. In this work, we present a one-pot synthetic approach for creating novel bipolar PAHs with extended π-conjugation, which are not accessible via conventional Pd-catalyzed routes.
View Article and Find Full Text PDFDistinct Fermi Resonance Patterns of Weak Coupling in 2D-IR Spectra of 5-Cyanoindole Revealed by Isotope Labeling.
J Phys Chem B
January 2025
Center for Ultrafast Science and Technology, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Fermi resonance is a common phenomenon, and a hidden caveat exists in the applications of infrared probes, causing spectral complication and shorter vibrational lifetime. In this work, using the cyanotryptophan (CNTrp) side chain model compound 5-cyanoindole (CN-5CNI), we performed Fourier transform infrared spectroscopy (FTIR) and two-dimensional infrared (2D-IR) spectroscopy on unlabeled CN-5CNI and its isotopically labeled substituents (CN-5CNI, CN-5CNI, CN-5CNI) and demonstrated the existence of Fermi resonance in 5CNI. By constructing the Hamiltonian and simulating 2D-IR spectra, we show that the distinct Fermi resonance 2D-IR patterns in various isotope substituents are determined by the quantum mixing consequences at the = 1 state, as well as the = 2 state, where the Fermi coupling and anharmonicity play a crucial role.
View Article and Find Full Text PDFIs There an Optimal Spacer Cation for Two-Dimensional Lead Iodide Perovskites?
ACS Mater Au
January 2025
Beijing National Laboratory for Molecular Science, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Two-dimensional lead iodide perovskites have attracted significant attention for their potential applications in optoelectronic and photonic devices due to their tunable excitonic properties. The choice of organic spacer cations significantly influences the light emission and exciton transport properties of these materials, which are vital for their device performance. In this Perspective, we discuss the impact of spacer cations on lattice dynamics and exciton-phonon coupling, focusing on three representative 2D lead iodide perovskites that exhibit distinct types of structural distortions.
View Article and Find Full Text PDFReviving the Lieb-Schultz-Mattis theorem in open quantum systems.
Natl Sci Rev
January 2025
Institute for Advanced Study, Tsinghua University, Beijing 100084, China.
In closed systems, the celebrated Lieb-Schultz-Mattis (LSM) theorem states that a one-dimensional locally interacting half-integer spin chain with translation and spin rotation symmetries cannot have a non-degenerate gapped ground state. However, the applicability of this theorem is diminished when the system interacts with a bath and loses its energy conservation. In this letter, we propose that the LSM theorem can be revived in the entanglement Hamiltonian when the coupling to the bath renders the system short-range correlated.
View Article and Find Full Text PDFMechanism, Performance, and Application of g-CN-Coupled TiO as an S-Scheme Heterojunction Photocatalyst for the Abatement of Gaseous Benzene.
ACS Appl Mater Interfaces
January 2025
Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-Gu, Seoul 04763, Republic of Korea.
In this research, S-scheme heterojunction photocatalysts are prepared through the hybridization of nitrogen-rich g-CN with TiO (coded as TCN-(): as the weight ratio of TiO:g-CN). The photocatalytic potential of TCN-() is evaluated against benzene (1-5 ppm) across varying humidity levels using a dynamic flow packed-bed photocatalytic reactor. Among the prepared composites, TCN-(10) exhibits the highest synergy between g-CN and TiO at "" ratio of 10%, showing superior best benzene degradation performance (e.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!