Trityl-Aryl-Nitroxide-Based Genuinely g-Engineered Biradicals, As Studied by Dynamic Nuclear Polarization, Multifrequency ESR/ENDOR, Arbitrary Wave Generator Pulse Microwave Waveform Spectroscopy, and Quantum Chemical Calculations
| Autor: | Olesya A. Krumkacheva, Vytautas Klimavicius, Ivan O. Timofeev, Elena Zaytseva, Olga Yu. Rogozhnikova, Kenji Sugisaki, Elena G. Bagryanskaya, Rei Hirao, Gerd Buntkowsky, Torsten Gutmann, Dmitry V. Trukhin, Victor M. Tormyshev, Shigeaki Nakazawa, Daisuke Shiomi, Kazuo Toyota, Hideto Matsuoka, Takeji Takui, Kazunobu Sato |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Nitroxide mediated radical polymerization
Zeeman effect 010304 chemical physics Spins Chemistry Nuclear magnetic resonance spectroscopy 010402 general chemistry 01 natural sciences Molecular physics 0104 chemical sciences symbols.namesake 0103 physical sciences symbols Physics::Chemical Physics Physical and Theoretical Chemistry Spectroscopy Hyperfine structure Microwave Quantum computer |
| Zdroj: | The Journal of Physical Chemistry A. 123:7507-7517 |
| ISSN: | 1520-5215 1089-5639 |
| DOI: | 10.1021/acs.jpca.9b07169 |
| Popis: | Trityl and nitroxide radicals are connected by π-topologically controlled aryl linkers, generating genuinely g-engineered biradicals. They serve as a typical model for biradicals in which the exchange (J) and hyperfine interactions compete with the g-difference electronic Zeeman interactions. The magnetic properties underlying the biradical spin Hamiltonian for solution, including J's, have been determined by multifrequency CW-ESR and 1H ENDOR spectroscopy and compared with those obtained by quantum chemical calculations. The experimental J values were in good agreement with the quantum chemical calculations. The g-engineered biradicals have been tested as a prototype for AWG (Arbitrary Wave Generator)-based spin manipulation techniques, which enable GRAPE (GRAdient Pulse Engineering) microwave control of spins in molecular magnetic resonance spectroscopy for use in molecular spin quantum computers, demonstrating efficient signal enhancement of specific weakened hyperfine signals. Dynamic nuclear polarization (DNP) effects of the biradicals for 400 MHz nuclear magnetic resonance signal enhancement have been examined, giving efficiency factors of 30 for 1H and 27.8 for 13C nuclei. The marked DNP results show the feasibility of these biradicals for hyperpolarization. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|