| Author: |
Alexey A. Popov
|
| Published in: | Springer International Publishing |
| Release Year: | 2017 |
| ISBN: | 978-3-319-47049-8 |
| Pages: | 333 |
| Edition: | First Edition |
| File Size: | 12 MB |
| File Type: | |
| Language: | English |
Description of Endohedral Fullerenes Electron Transfer and Spin
Over the last two decades, the research of endohedral fullerenes has made dramatic progress. Many types of endohedral fullerenes have been discovered, their production and separation techniques have been substantially improved, and comprehensive studies of their chemical and physical properties became possible. Encapsulation into the interior space of the fullerene cage stabilizes unique metal clusters or single atoms that are not known to exist in the free form. However, this stabilization is only partially achieved by the shielding of the species from the surrounding. Another important factor is that the carbon cage is not “innocent”.
Namely, the electron transfer between the encapsulated species and the carbon cage plays a crucial role in the structure and properties of endohedral metallofullerenes. Unprecedented molecular and electronic structure of endohedral fullerenes leads to a plethora of phenomena at the interface between the endohedral atoms and p-system of the carbon cage. Charge transfer in endohedral metallofullerene (EMF) molecules can either leave encapsulated species intact (i.e., only carbon cage is active as in empty fullerene) or proceed across the metal–cage interface, and examples of both types are well documented nowadays. The latter case is especially interesting since it opens the way to tune charge states of endohedral species while keeping a fullerene as a protecting shell around the redox center. Good electron-accepting properties of fullerenes made them attractive building blocks for organic electronics, and multiple studies of the EMF performance in this role have been carried out, from fundamental photophysical studies of the donor-acceptor dyads to the studies of the photoconversion efficiency in prototype bulk heterojunction solar cells. High thermal stability of endohedral metallofullerenes allows deposition of the molecules on various substrates in ultrahigh vacuum conditions and investigation of their electronic properties with high-resolution scanning probe and other surface science methods. Peculiar electronic states and dynamics of fullerene molecules and endohedral clusters could be investigated with the help of scanning tunneling microscopy.
Single-electron transfer is inevitably accompanied by the change of the spin state of the molecule, and here is another unique property of EMFs: the cage can either keep an unpaired spin itself, or it can transfer the spin to the endohedral cluster, and hence both the cage and the cluster spin states can be altered. Furthermore, encapsulation of the species with unpaired electrons (e.g., nitrogen or phosphorus atoms or lanthanide-containing clusters) brings endohedral fullerenes to the fields of molecular magnetism and quantum computing. Electron spin resonance, nuclear magnetic resonance, magnetometry, and X-ray magnetic circular dichroism have been used extensively to analyze spin-related phenomena in endohedral fullerenes.
Finally, well-defined spin state and long spin coherence make endohedral fullerenes with the nitrogen atom, such as N@C60, attractive for the field of quantum computing. The aim of Endohedral Fullerenes Electron Transfer and Spin book is a concise analysis of the behavior of the interface between encapsulated atoms and a carbon-based p-system under conditions of the electron transfer and description of the spin-based phenomena caused by the shielding of endohedral spins by the fullerene cage.
Namely, the electron transfer between the encapsulated species and the carbon cage plays a crucial role in the structure and properties of endohedral metallofullerenes. Unprecedented molecular and electronic structure of endohedral fullerenes leads to a plethora of phenomena at the interface between the endohedral atoms and p-system of the carbon cage. Charge transfer in endohedral metallofullerene (EMF) molecules can either leave encapsulated species intact (i.e., only carbon cage is active as in empty fullerene) or proceed across the metal–cage interface, and examples of both types are well documented nowadays. The latter case is especially interesting since it opens the way to tune charge states of endohedral species while keeping a fullerene as a protecting shell around the redox center. Good electron-accepting properties of fullerenes made them attractive building blocks for organic electronics, and multiple studies of the EMF performance in this role have been carried out, from fundamental photophysical studies of the donor-acceptor dyads to the studies of the photoconversion efficiency in prototype bulk heterojunction solar cells. High thermal stability of endohedral metallofullerenes allows deposition of the molecules on various substrates in ultrahigh vacuum conditions and investigation of their electronic properties with high-resolution scanning probe and other surface science methods. Peculiar electronic states and dynamics of fullerene molecules and endohedral clusters could be investigated with the help of scanning tunneling microscopy.
Single-electron transfer is inevitably accompanied by the change of the spin state of the molecule, and here is another unique property of EMFs: the cage can either keep an unpaired spin itself, or it can transfer the spin to the endohedral cluster, and hence both the cage and the cluster spin states can be altered. Furthermore, encapsulation of the species with unpaired electrons (e.g., nitrogen or phosphorus atoms or lanthanide-containing clusters) brings endohedral fullerenes to the fields of molecular magnetism and quantum computing. Electron spin resonance, nuclear magnetic resonance, magnetometry, and X-ray magnetic circular dichroism have been used extensively to analyze spin-related phenomena in endohedral fullerenes.
Finally, well-defined spin state and long spin coherence make endohedral fullerenes with the nitrogen atom, such as N@C60, attractive for the field of quantum computing. The aim of Endohedral Fullerenes Electron Transfer and Spin book is a concise analysis of the behavior of the interface between encapsulated atoms and a carbon-based p-system under conditions of the electron transfer and description of the spin-based phenomena caused by the shielding of endohedral spins by the fullerene cage.
Content of Endohedral Fullerenes Electron Transfer and Spin
1 Synthesis and Molecular Structures of Endohedral
Fullerenes............................................... 1
Alexey A. Popov
2 Electrochemistry and Frontier Molecular Orbitals
of Endohedral Metallofullerenes............................. 35
Alexey A. Popov
3 Non-Chromatographic Separation of Endohedral
Metallofullerenes by Utilizing Their Redox Properties........... 63
Nataliya Samoylova and Steven Stevenson
4 Ions of Endometallofullerenes in the Gas Phase ................ 81
Olga V. Boltalina
5 Photoexcitation in Donor-Acceptor Dyads Based on Endohedral
Fullerenes and Their Applications in Organic Photovoltaics ...... 103
Jieming Zhen, Qing Liu, and Shangfeng Yang
6 Scrutinizing the Endohedral Space: Superatom States
and Molecular Machines................................... 123
Min Feng and Hrvoje Petek
7 Electron Spin Resonance Studies of Metallofullerenes ........... 159
Taishan Wang and Chunru Wang
8 Electron Spin Resonance of Lanthanide EMFs................. 169
Tatsuhisa Kato
9 Ion Radicals of Endohedral Metallofullerenes Studied
by EPR Spectroscopy ..................................... 183
Alexey A. Popov
10 Nuclear Magnetic Resonance Spectroscopy of Endohedral
Metallofullerenes with Paramagnetic Metal Ions: Structure
Elucidation and Magnetic Anisotropy ........................ 199
Alexey A. Popov
11 Magnetic Properties of C80 Endofullerenes .................... 213
Rasmus Westerström and Thomas Greber
12 Nonmetallic Endofullerenes and the Endohedral Environment:
Structure, Dynamics, and Spin Chemistry..................... 229
Ronald G. Lawler
13 Preparation and Chemistry of N@C60........................ 265
Shen Zhou and Kyriakos Porfyrakis
14 Spin Quantum Computing with Endohedral Fullerenes.......... 297
Wolfgang Harnett
Index ...................................................... 325
Fullerenes............................................... 1
Alexey A. Popov
2 Electrochemistry and Frontier Molecular Orbitals
of Endohedral Metallofullerenes............................. 35
Alexey A. Popov
3 Non-Chromatographic Separation of Endohedral
Metallofullerenes by Utilizing Their Redox Properties........... 63
Nataliya Samoylova and Steven Stevenson
4 Ions of Endometallofullerenes in the Gas Phase ................ 81
Olga V. Boltalina
5 Photoexcitation in Donor-Acceptor Dyads Based on Endohedral
Fullerenes and Their Applications in Organic Photovoltaics ...... 103
Jieming Zhen, Qing Liu, and Shangfeng Yang
6 Scrutinizing the Endohedral Space: Superatom States
and Molecular Machines................................... 123
Min Feng and Hrvoje Petek
7 Electron Spin Resonance Studies of Metallofullerenes ........... 159
Taishan Wang and Chunru Wang
8 Electron Spin Resonance of Lanthanide EMFs................. 169
Tatsuhisa Kato
9 Ion Radicals of Endohedral Metallofullerenes Studied
by EPR Spectroscopy ..................................... 183
Alexey A. Popov
10 Nuclear Magnetic Resonance Spectroscopy of Endohedral
Metallofullerenes with Paramagnetic Metal Ions: Structure
Elucidation and Magnetic Anisotropy ........................ 199
Alexey A. Popov
11 Magnetic Properties of C80 Endofullerenes .................... 213
Rasmus Westerström and Thomas Greber
12 Nonmetallic Endofullerenes and the Endohedral Environment:
Structure, Dynamics, and Spin Chemistry..................... 229
Ronald G. Lawler
13 Preparation and Chemistry of N@C60........................ 265
Shen Zhou and Kyriakos Porfyrakis
14 Spin Quantum Computing with Endohedral Fullerenes.......... 297
Wolfgang Harnett
Index ...................................................... 325
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