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Hashikawa Y, Murata Y. Direct Through-Space Substituent-π Interactions in Noncovalent Arene-Fullerene Assemblies. Chem Asian J 2024; 19:e202400075. [PMID: 38385611 DOI: 10.1002/asia.202400075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/19/2024] [Accepted: 02/21/2024] [Indexed: 02/23/2024]
Abstract
The arene-arene interactions between electron-rich and deficient aromatics have been less understood. Herein, we focus on a [60]fullerene π-surface as an electron-deficient aromatics. Using a 1H signal of H2O@C60 as a magnetic probe, the presence of benzene-fullerene interactions was confirmed. To investigate substituent effects on the noncovalent arene-fullerene interactions, NMR titration experiments were carried out using an open-[60]fullerene and a series of substituted benzenes, i. e., PhX (X=NO2, CN, Cl, OMe, H, CH3, and NH2), demonstrating a 1 : 2 stoichiometry with a positive correlation between stabilization energies upon the first association (ΔG1) and Hammet constants (σm). The destabilization of the self-assembled structure for X=OMe with a σ-withdrawing nature clearly showed direct through-space substituent-π interactions describable by the Wheeler-Houk model while the second association was suggested to be considerably perturbed by the secondary effects.
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Affiliation(s)
- Yoshifumi Hashikawa
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Yasujiro Murata
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
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Vyas VK, Bacanu GR, Soundararajan M, Marsden ES, Jafari T, Shugai A, Light ME, Nagel U, Rõõm T, Levitt MH, Whitby RJ. Squeezing formaldehyde into C 60 fullerene. Nat Commun 2024; 15:2515. [PMID: 38514674 PMCID: PMC10957948 DOI: 10.1038/s41467-024-46886-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 03/13/2024] [Indexed: 03/23/2024] Open
Abstract
The cavity inside fullerene C60 provides a highly symmetric and inert environment for housing atoms and small molecules. Here we report the encapsulation of formaldehyde inside C60 by molecular surgery, yielding the supermolecular complex CH2O@C60, despite the 4.4 Å van der Waals length of CH2O exceeding the 3.7 Å internal diameter of C60. The presence of CH2O significantly reduces the cage HOMO-LUMO gap. Nuclear spin-spin couplings are observed between the fullerene host and the formaldehyde guest. The rapid spin-lattice relaxation of the formaldehyde 13C nuclei is attributed to a dominant spin-rotation mechanism. Despite being squeezed so tightly, the encapsulated formaldehyde molecules rotate freely about their long axes even at cryogenic temperatures, allowing observation of the ortho-to-para spin isomer conversion by infrared spectroscopy. The particle in a box nature of the system is demonstrated by the observation of two quantised translational modes in the cryogenic THz spectra.
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Affiliation(s)
- Vijyesh K Vyas
- School of Chemistry, University of Southampton, SO17 1BJ, Southampton, UK
| | - George R Bacanu
- School of Chemistry, University of Southampton, SO17 1BJ, Southampton, UK
| | | | | | - Tanzeeha Jafari
- National Institute of Chemical Physics and Biophysics, Akademia tee 23, 12618, Tallinn, Estonia
- Department of Cybernetics, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia
| | - Anna Shugai
- National Institute of Chemical Physics and Biophysics, Akademia tee 23, 12618, Tallinn, Estonia
| | - Mark E Light
- School of Chemistry, University of Southampton, SO17 1BJ, Southampton, UK
| | - Urmas Nagel
- National Institute of Chemical Physics and Biophysics, Akademia tee 23, 12618, Tallinn, Estonia
| | - Toomas Rõõm
- National Institute of Chemical Physics and Biophysics, Akademia tee 23, 12618, Tallinn, Estonia.
| | - Malcolm H Levitt
- School of Chemistry, University of Southampton, SO17 1BJ, Southampton, UK.
| | - Richard J Whitby
- School of Chemistry, University of Southampton, SO17 1BJ, Southampton, UK.
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Liu W, Huang G, Chen CY, Tan T, Fuyuki H, Hu S, Nakamura T, Truong MA, Murdey R, Hashikawa Y, Murata Y, Wakamiya A. An open-cage bis[60]fulleroid as an electron transport material for tin halide perovskite solar cells. Chem Commun (Camb) 2024; 60:2172-2175. [PMID: 38315560 DOI: 10.1039/d3cc05843c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
An open-cage bis[60]fulleroid (OC) was applied as an electron transport material (ETM) in tin (Sn) halide perovskite solar cells (PSCs). Due to the reduced offset between the energy levels of Sn-based perovskites and ETMs, the power conversion efficiency (PCE) of Sn-based PSCs with OC reached 9.6% with an open-circuit voltage (VOC) of 0.72 V. Additionally, OC exhibited superior thermal stability and provided 75% of the material without decomposition after vacuum deposition. The PSC using vacuum-deposited OC as the ETM could afford a PCE of 7.6%, which is a big leap forward compared with previous results using vacuum-deposited fullerene derivatives as ETMs.
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Affiliation(s)
- Wentao Liu
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Guanglin Huang
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Chien-Yu Chen
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Tiancheng Tan
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Harata Fuyuki
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Shuaifeng Hu
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Tomoya Nakamura
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Minh Anh Truong
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Richard Murdey
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Yoshifumi Hashikawa
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Yasujiro Murata
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Atsushi Wakamiya
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
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