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Despite the rapidly growing interest in exploiting millimeter and terahertz waves for wireless data transfer, the role of reflected non-line-of-sight (NLOS) paths in wireless networking is one of the least explored questions. In this paper, we investigate the idea of harnessing these specular NLOS paths for communication in directional networks at frequencies above 100 GHz. We explore several illustrative transmitter architectures, namely, a conventional substrate-lens dipole antenna and a leaky-wave antenna. We investigate how these high-gain directional antennas offer both new challenges and new opportunities for exploiting NLOS paths. Our results demonstrate the sensitivity to antenna alignment, power spectrum variations, and the disparity in supported bandwidth of various line-of-sight (LOS) and reflected path configurations. We show that NLOS paths can, under certain circumstances, offer even higher data rates than the conventional LOS path. This result illustrates the unique opportunities that distinguish THz wireless systems from those that operate at lower frequencies.
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This content will become publicly available on April 1, 2026
To Transfer or Not to Transfer an Electron: Anionic Metal Centers Reveal Dual Functionality for Polymerization Reactions
Catalysts with anionic metal centers have recently been proposed to enhance the performance of various chemical processes. Here, we focus on the reactivity of Co(CO)4− for the polymerization of aziridine and carbon monoxide to form polypeptoids, motivated by earlier experimental studies. We used multi-reference and density functional theory methods to investigate possible reaction mechanisms and provide insights into the role of the negatively charged cobalt center. Two different reaction paths were identified. In the first path, Co− acts as a nucleophile, donating an electron pair to the reaction substrate, while in the second path, it performs a single electron transfer to the substrate, initiating radical polymerization. The difference in the activation barriers for the two key steps is small and falls within the accuracy of our calculations. As suggested in the literature, solvent effects can play a primary role in determining the outcomes of such reactions. Future investigations will involve different metals or ligands and will investigate the effects of these two reaction paths on other chemical transformations.
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- Award ID(s):
- 1940456
- PAR ID:
- 10636404
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Molecules
- Volume:
- 30
- Issue:
- 7
- ISSN:
- 1420-3049
- Page Range / eLocation ID:
- 1570
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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