101
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Paschke F, Erler P, Enenkel V, Gragnaniello L, Fonin M. Bulk-Like Magnetic Signature of Individual Fe 4H Molecular Magnets on Graphene. ACS NANO 2019; 13:780-785. [PMID: 30604971 DOI: 10.1021/acsnano.8b08184] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Single-molecule magnets (SMMs) incorporate key properties that make them promising candidates for the emerging field of spintronics. The challenge to realize ordered SMM arrangements on surfaces and at the same time to preserve the magnetic properties upon interaction with the environment is a crucial point on the way to applications. Here we employ inelastic electron tunneling spectroscopy (IETS) to address the magnetic properties in single Fe4 complexes that are adsorbed in a highly ordered arrangement on graphene/Ir(111). We are able to substantially reduce the influence of both the tunneling tip and the adsorption environment on the Fe4 complex during the measurements by using appropriate tunneling parameters in combination with the flat-lying Fe4H derivative and a weakly interacting surface. This allows us to perform noninvasive IETS studies on these bulky molecules. From the measurements we identify intermultiplet spin transitions and determine the intramolecular magnetic exchange interaction constant on a large number of molecules. Although a considerable scattering of the exchange constant values is observed, the distribution maximum is located at a value that coincides with that of the bulk. Our findings confirm a retained molecular magnetism of the Fe4H complex at the local scale and evaluate the influence of the environment on the magnetic exchange interaction.
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Affiliation(s)
- Fabian Paschke
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
| | - Philipp Erler
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
| | - Vivien Enenkel
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
| | - Luca Gragnaniello
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
| | - Mikhail Fonin
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
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102
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Vijaykumar G, Bhunia M, Mandal SK. A phenalenyl-based nickel catalyst for the hydroboration of olefins under ambient conditions. Dalton Trans 2019; 48:5779-5784. [PMID: 30976767 DOI: 10.1039/c9dt00468h] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In this report, nickel-catalyzed hydroboration of vinylarenes and aliphatic alkenes is investigated. The non-innocent phenalenyl ligand moiety in the nickel complex Ni(PLY)2(THF)2 (1) was utilized as an electron reservoir for the selective hydroboration reaction in the presence of pinacolborane under ambient conditions. The mechanistic investigations revealed that the alkene hydroboration reaction takes place through a single electron transfer (SET) from the phenalenyl ligand backbone leading to the cleavage of the B-H bond.
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Affiliation(s)
- Gonela Vijaykumar
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India.
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103
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Meng X, Shi W, Cheng P. Magnetism in one-dimensional metal–nitronyl nitroxide radical system. Coord Chem Rev 2019. [DOI: 10.1016/j.ccr.2018.02.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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104
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Lach S, Altenhof A, Shi S, Fahlman M, Ziegler C. Electronic and magnetic properties of a ferromagnetic cobalt surface by adsorbing ultrathin films of tetracyanoethylene. Phys Chem Chem Phys 2019; 21:15833-15844. [PMID: 31282504 DOI: 10.1039/c9cp02205h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Ultrathin films of tetracyanoethylene (TCNE) on Co(100) were investigated by means of spin-integrated and spin-resolved photoemission spectroscopy ((sp-)UPS), X-ray photoemission spectroscopy (XPS), near edge X-ray absorption fine-structure spectroscopy (NEXAFS), and X-ray magnetic circular dichroism (XMCD). We found a coverage-dependent modulation of the interface dipole and a switching between a metallic and a resistive spin filtering at the interface triggered by two distinct adsorption geometries of TCNE. The strongest hybridization and spin structure modifications are found at low coverage with a face-on adsorption geometry indicating changes in the distance between the surface Co atoms beneath. TCNE has the potential to manipulate the magnetic moments in the Co surface itself, including the possibility of magnetic hardening effects. In summary, the system TCNE/Co offers an experimentally rather easy and controllable way to build up a stable molecular platform stabilizing the reactive ferromagnetic Co surface and customizing the electronic and magnetic properties of the resulting spinterface simultaneously. This makes this system very attractive for spintronic applications as an alternative, less reactive but highly spin polarized foundation beside graphene-based systems.
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Affiliation(s)
- Stefan Lach
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Kaiserslautern, 67663 Kaiserslautern, Germany.
| | - Anna Altenhof
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Kaiserslautern, 67663 Kaiserslautern, Germany.
| | - Shengwei Shi
- Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, 430205 Wuhan, China and Department of Physics, Chemistry and Biology, University of Linköping, Linköping, 58183 Linköping, Sweden
| | - Mats Fahlman
- Department of Physics, Chemistry and Biology, University of Linköping, Linköping, 58183 Linköping, Sweden
| | - Christiane Ziegler
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Kaiserslautern, 67663 Kaiserslautern, Germany.
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105
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Vardhanapu PK, Ahmed J, Jose A, Shaw BK, Sen TK, Mathews AA, Mandal SK. Phenalenyl Based Aluminum Compound for Catalytic C-H Arylation of Arene and Heteroarenes at Room Temperature. J Org Chem 2018; 84:289-299. [PMID: 30507198 DOI: 10.1021/acs.joc.8b02699] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Main group metal based catalysis has been considered to be a cost-effective alternative way to the transition metal based catalysis, due to the high abundance of main group metals in the Earth's crust. Among the main group metals, aluminum is the most abundant (7-8%) in the Earth's crust, making the development of aluminum based catalysts very attractive. So far, aluminum based compounds have been popularly used as Lewis acids in a variety of organic reactions, but chemical transformation demanding a redox based process has never utilized an Al(III) complex as a catalyst. Herein, we tuned the redox noninnocence behavior of a phenalenyl ligand by coupling with Al(III) ion, which subsequently can store the electron upon reduction with K to carry out direct C-H arylation of heteroarenes/mesitylene at ambient temperature. A mechanistic investigation revealed that a three-electron reduced phenalenyl based triradical aluminum(III) complex plays the key role in such catalysis. The electronic structure of the catalytically active triradical species has been probed using EPR spectroscopy, magnetic susceptibility measurements, and electronic structure calculations using a DFT method.
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Affiliation(s)
- Pavan K Vardhanapu
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Jasimuddin Ahmed
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Anex Jose
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Bikash Kumar Shaw
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Tamal K Sen
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Amita A Mathews
- Department of Chemical Sciences, Loyola College , University of Madras , Nungambakkam, Chennai - 600034 , India
| | - Swadhin K Mandal
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
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106
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Interfacial Spin Manipulation of Nickel-Quinonoid Complex Adsorbed on Co(001) Substrate. MAGNETOCHEMISTRY 2018. [DOI: 10.3390/magnetochemistry5010002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We studied the structural, electronic, and magnetic properties of a recently synthesized Ni(II)-quinonoid complex upon adsorption on a magnetic Co(001) substrate. Our density functional theory + U (DFT+U) calculations predict that the molecule undergoes a spin-state switching from low-spin S = 0 in the gas phase to high-spin S ≈ 1 when adsorbed on the Co(001) surface. A strong covalent interaction of the quinonoid rings and surface atoms leads to an increase of the Ni–O(N) bond lengths in the chemisorbed molecule that support the spin-state switching. Our DFT+U calculations show that the molecule is ferromagnetically coupled to the substrate. The Co surface–Ni center exchange mechanism was carefully investigated. We identified an indirect exchange interaction via the quinonoid ligands that stabilizes the molecule’s spin moment in ferromagnetic alignment with the Co surface magnetization.
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107
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Kertesz M. Pancake Bonding: An Unusual Pi‐Stacking Interaction. Chemistry 2018; 25:400-416. [DOI: 10.1002/chem.201802385] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 06/14/2018] [Indexed: 01/22/2023]
Affiliation(s)
- Miklos Kertesz
- Chemistry Department and Institute of Soft Matter Georgetown University 37th and O Streets NW Washington, DC 20057-1227 USA
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108
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Chakraborty S, Ahmed J, Shaw BK, Jose A, Mandal SK. An Iron-Based Long-Lived Catalyst for Direct C-H Arylation of Arenes and Heteroarenes. Chemistry 2018; 24:17651-17655. [PMID: 30246421 DOI: 10.1002/chem.201803402] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 09/06/2018] [Indexed: 11/06/2022]
Abstract
Direct C-H arylation of arenes and heteroarenes to biaryls at ambient temperature has been accomplished using a phenalenyl-supported iron(III) catalyst. The present catalyst requires a chemical reductant such as potassium and functions without any light stimulation. C-H arylation of various heteroarenes including pyridine as well as unactivated arene such as benzene delivered good to excellent yield (28 examples, up to 92 %) at room temperature. A combined effort based on experiments and theoretical calculations established that a phenalenyl-based radical species (generated by chemical reduction of the iron(III) coordinated phenalenyl complex) plays key role during the catalysis. Furthermore, this catalyst displayed remarkable stability during the catalysis, as evident from the fact that it was still usable over ten consecutive catalytic runs without losing its catalytic efficiency.
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Affiliation(s)
- Soumi Chakraborty
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-, 741246, India
| | - Jasimuddin Ahmed
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-, 741246, India
| | - Bikash Kumar Shaw
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-, 741246, India
| | - Anex Jose
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-, 741246, India
| | - Swadhin K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-, 741246, India
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109
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Antoni PW, Hansmann MM. Pyrylenes: A New Class of Tunable, Redox-Switchable, Photoexcitable Pyrylium–Carbene Hybrids with Three Stable Redox-States. J Am Chem Soc 2018; 140:14823-14835. [DOI: 10.1021/jacs.8b08545] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Patrick W. Antoni
- Georg-August Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Max M. Hansmann
- Georg-August Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
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110
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Dai YZ, Dong BW, Kao Y, Wang ZY, Un HI, Liu Z, Lin ZJ, Li L, Xie FB, Lu Y, Xu MX, Lei T, Sun YJ, Wang JY, Gao S, Jiang SD, Pei J. Chemical Modification toward Long Spin Lifetimes in Organic Conjugated Radicals. Chemphyschem 2018; 19:2972-2977. [PMID: 30085398 DOI: 10.1002/cphc.201800742] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Indexed: 11/11/2022]
Abstract
Organic semiconductors for spin-based devices require long spin relaxation times. Understanding their spin relaxation mechanisms is critical to organic spintronic devices and applications for quantum information processing. However, reports on the spin relaxation mechanisms of organic conjugated molecules are rare and the research methods are also limited. Herein, we study the molecular design and spin relaxation mechanisms by systematically varying the structure of a conjugated radical. We found that solid-state relaxation times of organic materials are largely different from that in solution state. We demonstrate that substitution of a lower gyromagnetic ratio nucleus (e. g. D, Cl) on the para-position of the aryl rings in the triphenylmethyl (TM) radical can significantly improve their coherence times (Tm ). Flexible thin films based on such radicals exhibit ultra-long spin-lattice relaxation times (T1 ) up to 35.6(6) μs and Tm up to 1.08(4) μs under ambient conditions, which are among the longest values in films. More importantly, using the TM radical derivative (5CM), we observed room-temperature quantum coherence and Rabi cycles in thin film for the first time, suggesting that organic conjugated radicals have great potentials for spin-based information processing.
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Affiliation(s)
- Ya-Zhong Dai
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center of Soft Matter Science and Engineering College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Bo-Wei Dong
- Beijing National Laboratory for Molecular Sciences (BNLMS), Beijing Key Laboratory for Magnetoelectric Materials and Devices, College of Chemistry and Molecular Engineering,Peking University, Beijing, 100871, China
| | - Yi Kao
- Beijing National Laboratory for Molecular Sciences (BNLMS), Beijing Key Laboratory for Magnetoelectric Materials and Devices, College of Chemistry and Molecular Engineering,Peking University, Beijing, 100871, China
| | - Zi-Yuan Wang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center of Soft Matter Science and Engineering College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Hio-Ieng Un
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center of Soft Matter Science and Engineering College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Zheng Liu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Beijing Key Laboratory for Magnetoelectric Materials and Devices, College of Chemistry and Molecular Engineering,Peking University, Beijing, 100871, China
| | - Zhi-Jun Lin
- State Key Laboratory of Membrane Biology Biodynamic Optical Imaging Center (BIOPIC) School of Life Sciences, Peking University, Beijing, 100871, People's Republic of China
| | - Liang Li
- Beijing National Laboratory for Molecular Sciences (BNLMS), Beijing Key Laboratory for Magnetoelectric Materials and Devices, College of Chemistry and Molecular Engineering,Peking University, Beijing, 100871, China
| | - Fang-Bai Xie
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center of Soft Matter Science and Engineering College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Yang Lu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center of Soft Matter Science and Engineering College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Mei-Xing Xu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Beijing Key Laboratory for Magnetoelectric Materials and Devices, College of Chemistry and Molecular Engineering,Peking University, Beijing, 100871, China
| | - Ting Lei
- Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing, 100871, People's Republic of China
| | - Yu-Jie Sun
- State Key Laboratory of Membrane Biology Biodynamic Optical Imaging Center (BIOPIC) School of Life Sciences, Peking University, Beijing, 100871, People's Republic of China
| | - Jie-Yu Wang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center of Soft Matter Science and Engineering College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Song Gao
- Beijing National Laboratory for Molecular Sciences (BNLMS), Beijing Key Laboratory for Magnetoelectric Materials and Devices, College of Chemistry and Molecular Engineering,Peking University, Beijing, 100871, China
| | - Shang-Da Jiang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Beijing Key Laboratory for Magnetoelectric Materials and Devices, College of Chemistry and Molecular Engineering,Peking University, Beijing, 100871, China
| | - Jian Pei
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center of Soft Matter Science and Engineering College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
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111
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Boukari S, Jabbar H, Schleicher F, Gruber M, Avedissian G, Arabski J, Da Costa V, Schmerber G, Rengasamy P, Vileno B, Weber W, Bowen M, Beaurepaire E. Disentangling Magnetic Hardening and Molecular Spin Chain Contributions to Exchange Bias in Ferromagnet/Molecule Bilayers. NANO LETTERS 2018; 18:4659-4663. [PMID: 29991266 DOI: 10.1021/acs.nanolett.8b00570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We performed ferromagnetic resonance and magnetometry experiments to clarify the relationship between two reported magnetic exchange effects arising from interfacial spin-polarized charge transfer in ferromagnetic metal (FM)/molecule bilayers: the magnetic hardening effect and spinterface-stabilized molecular spin chains. To disentangle these effects, we tuned the metal phthalocyanine molecule central site's magnetic moment to enhance or suppress the formation of spin chains in the molecular film. We find that both effects are distinct, and additive. In the process, we extend the list of FM/molecule candidate pairs that are known to generate magnetic exchange effects, experimentally confirm the predicted increase in anisotropy upon molecular adsorption, and show that spin chains within the molecular film can enhance magnetic exchange. Our results confirm, as an echo to progress regarding inorganic spintronic tunnelling, that spintronic tunnelling across structurally ordered organic barriers has been reached through previous magnetotransport experiments.
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Affiliation(s)
- Samy Boukari
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Hashim Jabbar
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Filip Schleicher
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Manuel Gruber
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Garen Avedissian
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Jacek Arabski
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Victor Da Costa
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Guy Schmerber
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Prashanth Rengasamy
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Bertrand Vileno
- Institut de Chimie de Strasbourg, Université de Strasbourg, CNRS UMR7177 , 4 rue Blaise Pascal , F-67081 Strasbourg Cedex , France
- French EPR Federation of Research (REseau NAtional de Rpe interDisciplinaire (RENARD), Fédération IR-RPE CNRS 3443) , 59655 Villeneuve d'Ascq Cedex , France
| | - Wolfgang Weber
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Martin Bowen
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
| | - Eric Beaurepaire
- Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43 , F-67034 Strasbourg Cedex 2 , France
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112
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Abstract
We describe a minimal realization of reversibly programmable matter in the form of a featureless smooth elastic plate that has the capacity to store information in a Braille-like format as a sequence of stable discrete dimples. Simple experiments with cylindrical and spherical shells show that we can control the number, location, and the temporal order of these dimples, which can be written and erased at will. Theoretical analysis of the governing equations in a specialized setting and numerical simulations of the complete equations allow us to characterize the phase diagram for the formation of these localized elastic states, elastic bits (e-bits), consistent with our observations. Given that the inherent bistability and hysteresis in these low-dimensional systems arise exclusively due to the geometrical-scale separation, independent of material properties or absolute scale, our results might serve as alternate approaches to small-scale mechanical memories.
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113
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Ahmed J, Chakraborty S, Jose A, P S, Mandal SK. Integrating Organic Lewis Acid and Redox Catalysis: The Phenalenyl Cation in Dual Role. J Am Chem Soc 2018; 140:8330-8339. [PMID: 29883115 DOI: 10.1021/jacs.8b04786] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In recent years, merging different types of catalysis in a single pot has drawn considerable attention and these catalytic processes have mainly relied upon metals. However, development of a completely metal free approach integrating organic redox and organic Lewis acidic property into a single system has been missing in the current literature. This study establishes that a redox active phenalenyl cation can activate one of the substrates by single electron transfer process while the same can activate the other substrate by a donor-acceptor type interaction using its Lewis acidity. This approach has successfully achieved light and metal-free catalytic C-H functionalization of unactivated arenes at ambient temperature (39 entries, including core moiety of a top-selling molecule boscalid), an economically attractive alternative to the rare metal-based multicatalysts process. A tandem approach involving trapping of reaction intermediates, spectroscopy along with density functional theory calculations unravels the dual role of phenalenyl cation.
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Affiliation(s)
- Jasimuddin Ahmed
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Soumi Chakraborty
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Anex Jose
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Sreejyothi P
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
| | - Swadhin K Mandal
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur - 741246 , India
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114
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Tang YH, Lin CJ, Chiang KR. Hard-hard coupling assisted anomalous magnetoresistance effect in amine-ended single-molecule magnetic junction. J Chem Phys 2018; 146:224701. [PMID: 29166063 DOI: 10.1063/1.4984821] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We proposed a single-molecule magnetic junction (SMMJ), composed of a dissociated amine-ended benzene sandwiched between two Co tip-like nanowires. To better simulate the break junction technique for real SMMJs, the first-principles calculation associated with the hard-hard coupling between a amine-linker and Co tip-atom is carried out for SMMJs with mechanical strain and under an external bias. We predict an anomalous magnetoresistance (MR) effect, including strain-induced sign reversal and bias-induced enhancement of the MR value, which is in sharp contrast to the normal MR effect in conventional magnetic tunnel junctions. The underlying mechanism is the interplay between four spin-polarized currents in parallel and anti-parallel magnetic configurations, originated from the pronounced spin-up transmission feature in the parallel case and spiky transmission peaks in other three spin-polarized channels. These intriguing findings may open a new arena in which magnetotransport and hard-hard coupling are closely coupled in SMMJs and can be dually controlled either via mechanical strain or by an external bias.
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Affiliation(s)
- Y-H Tang
- Department of Physics, National Central University, Jung-Li 32001, Taiwan
| | - C-J Lin
- Department of Physics, National Central University, Jung-Li 32001, Taiwan
| | - K-R Chiang
- Department of Physics, National Central University, Jung-Li 32001, Taiwan
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115
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Mou Z, Kertesz M. Sigma‐ versus Pi‐Dimerization Modes of Triangulene. Chemistry 2018; 24:6140-6147. [DOI: 10.1002/chem.201705763] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Zhongyu Mou
- Department of Chemistry and Institute of Soft Matter Georgetown University Washington DC 20057 USA
| | - Miklos Kertesz
- Department of Chemistry and Institute of Soft Matter Georgetown University Washington DC 20057 USA
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116
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Rohlf S, Gruber M, Flöser BM, Grunwald J, Jarausch S, Diekmann F, Kalläne M, Jasper-Toennies T, Buchholz A, Plass W, Berndt R, Tuczek F, Rossnagel K. Light-Induced Spin Crossover in an Fe(II) Low-Spin Complex Enabled by Surface Adsorption. J Phys Chem Lett 2018; 9:1491-1496. [PMID: 29510617 DOI: 10.1021/acs.jpclett.8b00338] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Understanding and controlling the spin-crossover properties of molecular complexes can be of particular interest for potential applications in molecular spintronics. Using near-edge X-ray absorption fine structure spectroscopy, we investigated these properties for a new vacuum-evaporable Fe(II) complex, namely [Fe(pypyr(CF3)2)2(phen)] (pypyr = 2-(2'-pyridyl)pyrrolide, phen = 1,10-phenanthroline). We find that the spin-transition temperature, well above room temperature for the bulk compound, is drastically lowered for molecules arranged in thin films. Furthermore, while within the experimentally accessible temperature range (2 K < T < 410 K) the bulk material shows indication of neither light-induced excited spin-state trapping nor soft X-ray-induced excited spin-state trapping, these effects are observed for molecules within thin films up to temperatures around 100 K. Thus, by arranging the molecules into thin films, a nominal low-spin complex is effectively transformed into a spin-crossover complex.
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Affiliation(s)
- Sebastian Rohlf
- Institut für Experimentelle und Angewandte Physik , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Manuel Gruber
- Institut für Experimentelle und Angewandte Physik , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Benedikt M Flöser
- Institut für Anorganische Chemie , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Jan Grunwald
- Institut für Anorganische Chemie , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Simon Jarausch
- Institut für Experimentelle und Angewandte Physik , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Florian Diekmann
- Institut für Experimentelle und Angewandte Physik , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Matthias Kalläne
- Institut für Experimentelle und Angewandte Physik , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
- Ruprecht-Haensel-Labor , Christian-Albrechts-Universität zu Kiel und Deutsches Elektronen-Synchrotron DESY , 24098 Kiel und 22607 Hamburg , Germany
| | - Torben Jasper-Toennies
- Institut für Experimentelle und Angewandte Physik , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Axel Buchholz
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität , 07743 Jena , Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität , 07743 Jena , Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Felix Tuczek
- Institut für Anorganische Chemie , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
| | - Kai Rossnagel
- Institut für Experimentelle und Angewandte Physik , Christian-Albrechts-Universität zu Kiel , 24098 Kiel , Germany
- Ruprecht-Haensel-Labor , Christian-Albrechts-Universität zu Kiel und Deutsches Elektronen-Synchrotron DESY , 24098 Kiel und 22607 Hamburg , Germany
- Deutsches Elektronen-Synchrotron DESY , 22607 Hamburg , Germany
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117
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Bates D, Robertson CM, Leitch AA, Dube PA, Oakley RT. Magnetic Bistability in Naphtho-1,3,2-dithiazolyl: Solid State Interconversion of a Thiazyl π-Radical and Its N–N σ-Bonded Dimer. J Am Chem Soc 2018. [DOI: 10.1021/jacs.7b13699] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Demetris Bates
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, United Kingdom
| | - Craig M. Robertson
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, United Kingdom
| | - Alicea A. Leitch
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Paul A. Dube
- Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Richard T. Oakley
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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118
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Forment-Aliaga A, Coronado E. Hybrid Interfaces in Molecular Spintronics. CHEM REC 2018; 18:737-748. [DOI: 10.1002/tcr.201700109] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 02/16/2018] [Indexed: 01/08/2023]
Affiliation(s)
- Alicia Forment-Aliaga
- Instituto de Ciencia Molecular; Universitat de València; C/ Catedrático José Beltrán, 2. 46980 Paterna Spain
| | - Eugenio Coronado
- Instituto de Ciencia Molecular; Universitat de València; C/ Catedrático José Beltrán, 2. 46980 Paterna Spain
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119
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Banik A, Paira R, Shaw BK, Vijaykumar G, Mandal SK. Accessing Heterobiaryls through Transition-Metal-Free C-H Functionalization. J Org Chem 2018; 83:3236-3244. [PMID: 29436824 DOI: 10.1021/acs.joc.8b00140] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Herein we report a transition-metal-free synthetic protocol for heterobiaryls, one of the most important pharmacophores in the modern drug industry, employing a new multidonor phenalenyl (PLY)-based ligand. The current procedure offers a wide substrate scope (24 examples) with a low catalyst loading resulting in an excellent product yield (up to 95%). The reaction mechanism involves a single electron transfer (SET) from a phenalenyl-based radical to generate a reactive heteroaryl radical. To establish the mechanism, we have isolated the catalytically active SET initiator, characterizing by a magnetic study.
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Affiliation(s)
- Ananya Banik
- Department of Chemical Sciences , Indian Institute of Science Education and Research , Kolkata , Mohanpur 741246 , India
| | - Rupankar Paira
- Department of Chemistry , Maharaja Manindra Chandra College , 20 Ramkanto Bose Street , Kolkata 700003 , India
| | - Bikash Kumar Shaw
- Department of Chemical Sciences , Indian Institute of Science Education and Research , Kolkata , Mohanpur 741246 , India
| | - Gonela Vijaykumar
- Department of Chemical Sciences , Indian Institute of Science Education and Research , Kolkata , Mohanpur 741246 , India
| | - Swadhin K Mandal
- Department of Chemical Sciences , Indian Institute of Science Education and Research , Kolkata , Mohanpur 741246 , India
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120
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Kuzmin SM, Chulovskaya SA, Parfenyuk VI. Structures and properties of porphyrin-based film materials part I. The films obtained via vapor-assisted methods. Adv Colloid Interface Sci 2018; 253:23-34. [PMID: 29444750 DOI: 10.1016/j.cis.2018.02.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 02/01/2018] [Accepted: 02/01/2018] [Indexed: 01/21/2023]
Abstract
This review is devoted to porphyrin-based film materials. Various technological and scientific applications of ones are close to surface and interface related phenomena. In the part I of review the following topics are discussed the recent progress in field of submonolayers, monolayers and multilayers films on the vapor-solid interfaces, including results on (i) conformational behavior of adsorbed molecules, (ii) aggregation and surface phases formation, (iii) on-surface coordination networks, and (iv) on-surface chemical reactions. The examples of combined approaches to developing materials and porphyrin-based film materials application are also presented.
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Affiliation(s)
- S M Kuzmin
- G.A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences, Ivanovo, Russia; Ivanovo State Power Engineering University, Ivanovo, Russia.
| | - S A Chulovskaya
- G.A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences, Ivanovo, Russia
| | - V I Parfenyuk
- G.A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences, Ivanovo, Russia; Kostroma State University, Kostroma, Russia
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121
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Sharma V, Som N, Dabhi SD, Jha PK. Tailoring the Electronic and Magnetic Properties of Peculiar Triplet Ground State Polybenzoid “Triangulene”. ChemistrySelect 2018. [DOI: 10.1002/slct.201703054] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Vaishali Sharma
- Department of Physics; Faculty of Science; The Maharaja Sayajirao University of Baroda; Vadodara-390002 Gujarat India
| | - Narayan Som
- Department of Physics; Faculty of Science; The Maharaja Sayajirao University of Baroda; Vadodara-390002 Gujarat India
| | - Shweta D Dabhi
- Department of Physics; M K Bhavnagar University; Bhavnagar-364001 Gujarat India
| | - Prafulla K Jha
- Department of Physics; Faculty of Science; The Maharaja Sayajirao University of Baroda; Vadodara-390002 Gujarat India
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122
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Cao LL, Bamford KL, Liu LL, Stephan DW. Zinc-Containing Radical Anions via Single Electron Transfer to Donor-Acceptor Adducts. Chemistry 2018; 24:3980-3983. [DOI: 10.1002/chem.201800607] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Indexed: 01/08/2023]
Affiliation(s)
- Levy L. Cao
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
| | - Karlee L. Bamford
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
| | - Liu Leo Liu
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
| | - Douglas W. Stephan
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
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123
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Pedrini A, Poggini L, Tudisco C, Torelli M, Giuffrida AE, Bertani F, Cimatti I, Otero E, Ohresser P, Sainctavit P, Suman M, Condorelli GG, Mannini M, Dalcanale E. Self-Assembly of TbPc 2 Single-Molecule Magnets on Surface through Multiple Hydrogen Bonding. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:1702572. [PMID: 29226595 DOI: 10.1002/smll.201702572] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 09/26/2017] [Indexed: 06/07/2023]
Abstract
The complexation between 2-ureido-4[1H]-pyrimidinone (UPy) and 2,7-diamido-1,8-naphthyridine (NaPy) is used to promote the mild chemisorption of a UPy-functionalized terbium(III) double decker system on a silicon surface. The adopted strategy allows the single-molecule magnet behavior of the system to be maintained unaltered on the surface.
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Affiliation(s)
- Alessandro Pedrini
- Department of Chemistry, Life Sciences and Environmental Sustainability & INSTM RU of Parma, Parco delle Scienze 17/A, 43124, Parma, Italy
| | - Lorenzo Poggini
- Department of Chemistry "Ugo Schiff" & INSTM RU of Firenze University of Firenze, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Cristina Tudisco
- Department of Chemical Science & INSTM RU of Catania, University of Catania, Viale Andrea Doria 6, Catania, Italy
| | - Martina Torelli
- Department of Chemistry, Life Sciences and Environmental Sustainability & INSTM RU of Parma, Parco delle Scienze 17/A, 43124, Parma, Italy
| | - Antonino E Giuffrida
- Department of Chemical Science & INSTM RU of Catania, University of Catania, Viale Andrea Doria 6, Catania, Italy
| | - Federico Bertani
- Department of Chemistry, Life Sciences and Environmental Sustainability & INSTM RU of Parma, Parco delle Scienze 17/A, 43124, Parma, Italy
| | - Irene Cimatti
- Department of Chemistry "Ugo Schiff" & INSTM RU of Firenze University of Firenze, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Edwige Otero
- Synchrotron SOLEIL, L'Orme des Merisiers Saint Aubin, BP 48, 91192, Gif sur Yvette, France
| | - Philippe Ohresser
- Synchrotron SOLEIL, L'Orme des Merisiers Saint Aubin, BP 48, 91192, Gif sur Yvette, France
| | - Philippe Sainctavit
- Synchrotron SOLEIL, L'Orme des Merisiers Saint Aubin, BP 48, 91192, Gif sur Yvette, France
- IMPMC-UMR7590, CNRS, UPMC, IRD, MNHN, 4 place Jussieu, 75005, Paris, France
| | - Michele Suman
- Barilla G.R. F.lli SpA, Advanced Laboratory Research, Via Mantova 166, 43122, Parma, Italy
| | - Guglielmo G Condorelli
- Department of Chemical Science & INSTM RU of Catania, University of Catania, Viale Andrea Doria 6, Catania, Italy
| | - Matteo Mannini
- Department of Chemistry "Ugo Schiff" & INSTM RU of Firenze University of Firenze, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Enrico Dalcanale
- Department of Chemistry, Life Sciences and Environmental Sustainability & INSTM RU of Parma, Parco delle Scienze 17/A, 43124, Parma, Italy
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124
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Vijaykumar G, Pariyar A, Ahmed J, Shaw BK, Adhikari D, Mandal SK. Tuning the redox non-innocence of a phenalenyl ligand toward efficient nickel-assisted catalytic hydrosilylation. Chem Sci 2018; 9:2817-2825. [PMID: 29732067 PMCID: PMC5914464 DOI: 10.1039/c7sc04687a] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/30/2018] [Indexed: 01/02/2023] Open
Abstract
The hydrosilylation of olefins by a nickel(ii) catalyst assisted by a redox non-innocent phenalenyl (PLY) ligand is reported.
In this report, a ligand-redox assisted catalytic hydrosilylation has been investigated. A phenalenyl ligand coordinated nickel complex has been utilized as an electron reservoir to develop a base metal-assisted catalyst, which very efficiently hydrosilylates a wide variety of olefin substrates under ambient conditions. A mechanistic investigation revealed that a two-electron reduced phenalenyl based biradical nickel complex plays the key role in such catalysis. The electronic structure of the catalytically active biradical species has been interrogated using EPR spectroscopy, magnetic susceptibility measurements, and electronic structure calculations using a DFT method. Inhibition of the reaction by a radical quencher, as well as the mass spectrometric detection of two intermediates along the catalytic loop, suggest that a single electron transfer from the ligand backbone initiates the catalysis. The strategy of utilising the redox reservoir property of the ligand ensures that the nickel is not promoted to an unfavorable oxidation state, and the fine tuning between the ligand and metal redox orbitals elicits smooth catalysis.
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Affiliation(s)
- Gonela Vijaykumar
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur-741246 , India .
| | - Anand Pariyar
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur-741246 , India .
| | - Jasimuddin Ahmed
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur-741246 , India .
| | - Bikash Kumar Shaw
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur-741246 , India .
| | - Debashis Adhikari
- Department of Chemical Sciences , Indian Institute of Science Education and Research Mohali , SAS Nagar 140306 , India .
| | - Swadhin K Mandal
- Department of Chemical Sciences , Indian Institute of Science Education and Research-Kolkata , Mohanpur-741246 , India .
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125
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Sahoo MPK, Zhang Y, Wang J. Nanoscale magnetism and novel electronic properties of a bilayer bismuth(111) film with vacancies and chemical doping. Phys Chem Chem Phys 2018; 18:20550-61. [PMID: 27406933 DOI: 10.1039/c6cp03056d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Magnetically doped topological insulators (TIs) exhibit several exotic phenomena including the magnetoelectric effect and quantum anomalous Hall effect. However, from an experimental perspective, incorporation of spin moment into 3D TIs is still challenging. Thus, instead of 3D TIs, the 2D form of TIs may open up new opportunities to induce magnetism. Based on first principles calculations, we demonstrate a novel strategy to realize robust magnetism and exotic electronic properties in a 2D TI [bilayer Bi(111) film: abbreviated as Bi(111)]. We examine the magnetic and electronic properties of Bi(111) with defects such as bismuth monovacancies (MVs) and divacancies (DVs), and these defects decorated with 3d transition metals (TMs). It has been observed that the MV in Bi(111) can induce novel half metallicity with a net magnetic moment of 1 μB. The origin of half metallicity and magnetism in MV/Bi(111) is further explained by the passivation of the σ-dangling bonds near the defect site. Furthermore, in spite of the nonmagnetic nature of DVs, the TMs (V, Cr, Mn, and Fe) trapped at the 5/8/5 defect structure of DVs can not only yield a much higher spin moment than those trapped at the MVs but also display intriguing electronic properties such as metallic, semiconducting and spin gapless semiconducting properties. The predicted magnetic and electronic properties of TM/DV/Bi(111) systems are explained through density of states, spin density distribution and Bader charge analysis.
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Affiliation(s)
- M P K Sahoo
- Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, 38 Zheda Road, Hangzhou 310007, China. and Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Zhejiang University, 38 Zheda Road, Hangzhou 310007, China and Department of Physics, RGUKT IIIT, Nuzvid Campus, Andhra Pradesh, India
| | - Yajun Zhang
- Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, 38 Zheda Road, Hangzhou 310007, China.
| | - Jie Wang
- Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, 38 Zheda Road, Hangzhou 310007, China. and Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Zhejiang University, 38 Zheda Road, Hangzhou 310007, China
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126
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Moneo-Corcuera A, Nieto-Castro D, Sáenz de Pipaón C, Gómez V, Maldonado-Illescas P, Galan-Mascaros JR. Tuning the spin crossover behavior of the polyanion [(H2O)6Fe3(μ-L)6]6–: the case of the cesium salt. Dalton Trans 2018; 47:11895-11902. [DOI: 10.1039/c8dt01339j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cation exchange transforms the gradual spin transition of the trimer [(H2O)6Fe3(μ-L)6]6– into an abrupt transition with a wide hysteresis above room temperature.
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Affiliation(s)
- Andrea Moneo-Corcuera
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology (BIST)
- 43007 Tarragona
- Spain
| | - David Nieto-Castro
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology (BIST)
- 43007 Tarragona
- Spain
| | - Cristina Sáenz de Pipaón
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology (BIST)
- 43007 Tarragona
- Spain
| | - Verónica Gómez
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology (BIST)
- 43007 Tarragona
- Spain
| | - Pilar Maldonado-Illescas
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology (BIST)
- 43007 Tarragona
- Spain
| | - Jose Ramon Galan-Mascaros
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology (BIST)
- 43007 Tarragona
- Spain
- ICREA
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127
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Abadía M, Ilyn M, Piquero-Zulaica I, Gargiani P, Rogero C, Ortega JE, Brede J. Polymerization of Well-Aligned Organic Nanowires on a Ferromagnetic Rare-Earth Surface Alloy. ACS NANO 2017; 11:12392-12401. [PMID: 29161499 DOI: 10.1021/acsnano.7b06374] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The high reactivity of magnetic substrates toward molecular overlayers has so far inhibited the realization of more sophisticated on-surface reactions, thereby depriving these interfaces of a significant class of chemically tailored organics such as graphene nanoribbons, oligonuclear spin-chains, and metal-organic networks. Here, we present a multitechnique characterization of the polymerization of 4,4″-dibromo-p-terphenyl precursors into ordered poly(p-phenylene) arrays on top of the bimetallic GdAu2 surface alloy. The activation temperatures for bromine scission and subsequent homocoupling of molecular precursors were followed by temperature-dependent X-ray photoelectron spectroscopy. The structural characterizations of supramolecular and polymeric phases, performed by low-energy electron diffraction and scanning tunneling microscopy, establish an extraordinary degree of order extending into the mesoscale. Taking advantage of the high homogeneity, the electronic structure of the valence band was determined with angle-resolved photoemission spectroscopy. Importantly, the transition of localized molecular orbitals into a highly dispersive π-band, the fingerprint of successful polymerization, was observed while leaving all surface-related bands intact. Moreover, ferromagnetic ordering in the GdAu2 alloy was demonstrated for all phases by X-ray absorption spectroscopy. The transfer of well-established in situ methods for growing covalently bonded macromolecules with atomic precision onto magnetic rare-earth alloys is an important step toward toward studying and controlling intrinsic carbon- and rare-earth-based magnetism.
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Affiliation(s)
- Mikel Abadía
- Centro de Física de Materiales CFM - MPC, Centro Mixto CSIC-UPV/EHU , Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
| | - Maxim Ilyn
- Centro de Física de Materiales CFM - MPC, Centro Mixto CSIC-UPV/EHU , Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Donostia International Physics Center , Paseo Manuel Lardizabal 4, E-20018 San Sebastián, Spain
| | - Ignacio Piquero-Zulaica
- Centro de Física de Materiales CFM - MPC, Centro Mixto CSIC-UPV/EHU , Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
| | - Pierluigi Gargiani
- ALBA Synchrotron Light Source , Carretera BP 1413 km 3.3, E-08290 Cerdanyola del Vallés, Spain
| | - Celia Rogero
- Centro de Física de Materiales CFM - MPC, Centro Mixto CSIC-UPV/EHU , Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Donostia International Physics Center , Paseo Manuel Lardizabal 4, E-20018 San Sebastián, Spain
| | - José Enrique Ortega
- Centro de Física de Materiales CFM - MPC, Centro Mixto CSIC-UPV/EHU , Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Donostia International Physics Center , Paseo Manuel Lardizabal 4, E-20018 San Sebastián, Spain
- Departamento Física Aplicada I, Universidad del País Vasco , 20018 San Sebastián, Spain
| | - Jens Brede
- Centro de Física de Materiales CFM - MPC, Centro Mixto CSIC-UPV/EHU , Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
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128
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Jasper-Toennies T, Gruber M, Karan S, Jacob H, Tuczek F, Berndt R. Robust and Selective Switching of an Fe III Spin-Crossover Compound on Cu 2N/Cu(100) with Memristance Behavior. NANO LETTERS 2017; 17:6613-6619. [PMID: 29023129 DOI: 10.1021/acs.nanolett.7b02481] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The switching between two spin states makes spin-crossover molecules on surfaces very attractive for potential applications in molecular spintronics. Using scanning tunneling microscopy, the successful deposition of [Fe(pap)2]+ (pap = N-2-pyridylmethylidene-2-hydroxyphenylaminato) molecules on Cu2N/Cu(100) surface is evidenced. The deposited FeIII spin-crossover compound is controllably switched between three different states, each of them exhibiting a characteristic tunneling conductance. The conductance is therefore employed to readily read the state of the molecules. A comparison of the experimental data with the results of density functional theory calculations reveals that all Fe(pap)2 molecules are initially in their high-spin state. The two other states are compatible with the low-spin state of the molecule but differ with respect to their coupling to the substrate. As a proof of concept, the reversible and selective nature of the switching is used to build a two-molecule memory.
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Affiliation(s)
| | | | - Sujoy Karan
- Institute of Experimental and Applied Physics, University of Regensburg , 93053 Regensburg, Germany
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129
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Knaak T, Gruber M, Lindström C, Bocquet ML, Heck J, Berndt R. Ligand-Induced Energy Shift and Localization of Kondo Resonances in Cobalt-Based Complexes on Cu(111). NANO LETTERS 2017; 17:7146-7151. [PMID: 29045149 DOI: 10.1021/acs.nanolett.7b04181] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Magnetic sandwich complexes are of particular interest for molecular spintronics. Using scanning tunneling microscopy, we evidence the successful deposition of 1,3,5-tris(η6-borabenzene-η5-cyclopentadienylcobalt) benzene, a molecule composed of three connected magnetic sandwich units, on Cu(111). Scanning tunneling spectra reveal two distinct spatial-dependent narrow resonances close to the Fermi level for the trimer molecules as well as for molecular fragments composed of one and two magnetic units. With the help of density functional theory, these resonances are interpreted as two Kondo resonances originating from two distinct nondegenerate d-like orbitals. These Kondo resonances are found to have defined spatial extents dictated by the hybridization of the involved orbitals with that of the ligands. These results opens promising perspectives for investigating complex Kondo systems composed of several "Kondo" orbitals.
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Affiliation(s)
- Thomas Knaak
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , Leibnizstrasse 19, 24098 Kiel, Germany
| | - Manuel Gruber
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , Leibnizstrasse 19, 24098 Kiel, Germany
| | - Christoph Lindström
- Institut für Anorganische und Angewandte Chemie, Universität Hamburg , Martin-Luther-King-Platz 6, 20146 Hamburg, Germany
| | - Marie-Laure Bocquet
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC Université Paris 06, CNRS , 75005 Paris, France
| | - Jürgen Heck
- Institut für Anorganische und Angewandte Chemie, Universität Hamburg , Martin-Luther-King-Platz 6, 20146 Hamburg, Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , Leibnizstrasse 19, 24098 Kiel, Germany
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130
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Ahmed J, P S, Vijaykumar G, Jose A, Raj M, Mandal SK. A new face of phenalenyl-based radicals in the transition metal-free C-H arylation of heteroarenes at room temperature: trapping the radical initiator via C-C σ-bond formation. Chem Sci 2017; 8:7798-7806. [PMID: 29163916 PMCID: PMC5674448 DOI: 10.1039/c7sc02661g] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/12/2017] [Indexed: 01/02/2023] Open
Abstract
The radical-mediated transition metal-free approach for the direct C-H bond functionalization of arenes is considered as a cost effective alternative to transition metal-based catalysis. An organic ligand-based radical plays a key role by generating an aryl radical which undergoes a subsequent functionalization process. The design principle of the present study takes advantage of a relatively stable odd alternant hydrocarbon-based phenalenyl (PLY) radical. In this study, the first transition metal-free catalyzed direct C-H arylation of a variety of heteroarenes such as azoles, furan, thiophene and pyridine at room temperature has been reported using a phenalenyl-based radical without employing any photoactivation step. This protocol has been successfully applied to the gram scale synthesis of core moieties of bioactive molecules. The phenalenyl-based radical initiator has been characterized crystallographically by trapping it via the formation of a C-C σ-bond between the phenalenyl radical and solvent-based radical species.
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Affiliation(s)
- Jasimuddin Ahmed
- Department of Chemical Sciences , Indian Institute of Science Education and Research Kolkata , Mohanpur-741246 , Kolkata , India . http://swadhin-mandal.weebly.com/ ;
| | - Sreejyothi P
- Department of Chemical Sciences , Indian Institute of Science Education and Research Kolkata , Mohanpur-741246 , Kolkata , India . http://swadhin-mandal.weebly.com/ ;
| | - Gonela Vijaykumar
- Department of Chemical Sciences , Indian Institute of Science Education and Research Kolkata , Mohanpur-741246 , Kolkata , India . http://swadhin-mandal.weebly.com/ ;
| | - Anex Jose
- Department of Chemical Sciences , Indian Institute of Science Education and Research Kolkata , Mohanpur-741246 , Kolkata , India . http://swadhin-mandal.weebly.com/ ;
| | - Manthan Raj
- Zakir Husain Delhi College , University of Delhi , Delhi-110002 , India
| | - Swadhin K Mandal
- Department of Chemical Sciences , Indian Institute of Science Education and Research Kolkata , Mohanpur-741246 , Kolkata , India . http://swadhin-mandal.weebly.com/ ;
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131
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Wei H, Liu Y, Gopalakrishna TY, Phan H, Huang X, Bao L, Guo J, Zhou J, Luo S, Wu J, Zeng Z. B–N–B Bond Embedded Phenalenyl and Its Anions. J Am Chem Soc 2017; 139:15760-15767. [DOI: 10.1021/jacs.7b07375] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Haipeng Wei
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, People’s Republic of China
| | - Yulan Liu
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, People’s Republic of China
| | | | - Hoa Phan
- Department
of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore
| | - Xiaobo Huang
- College
of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, People’s Republic of China
| | - Lipiao Bao
- State Key Laboratory of Materials Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, People’s Republic of China
| | - Jing Guo
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, People’s Republic of China
| | - Jun Zhou
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, People’s Republic of China
| | - Shenglian Luo
- College
of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang 330063, People’s Republic of China
| | - Jishan Wu
- Department
of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore
| | - Zebing Zeng
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, People’s Republic of China
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132
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Martín-Olivera L, Shchukin DG, Teobaldi G. Role of Metal Lattice Expansion and Molecular π-Conjugation for the Magnetic Hardening at Cu-Organics Interfaces. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2017; 121:23777-23787. [PMID: 29152033 PMCID: PMC5682901 DOI: 10.1021/acs.jpcc.7b08476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 09/25/2017] [Indexed: 06/07/2023]
Abstract
Magnetic hardening and generation of room-temperature ferromagnetism at the interface between originally nonmagnetic transition metals and π-conjugated organics is understood to be promoted by interplay between interfacial charge transfer and relaxation-induced distortion of the metal lattice. The relative importance of the two contributions for magnetic hardening of the metal remains unquantified. Here, we disentangle their role via density functional theory simulation of several models of interfaces between Cu and polymers of different steric hindrance, π-conjugation, and electron-accepting properties: polyethylene, polyacetylene, polyethylene terephthalate, and polyurethane. In the absence of charge transfer, expansion and compression of the Cu face-centered cubic lattice is computed to lead to magnetic hardening and softening, respectively. Contrary to expectations based on the extent of π-conjugation on the organic and resulting charge transfer, the computed magnetic hardening is largest for Cu interfaced with polyethylene and smallest for the Cu-polyacetylene systems as a result of a differently favorable rehybridization leading to different enhancement of exchange interactions and density of states at the Fermi level. It thus transpires that neither the presence of molecular π-conjugation nor substantial charge transfer may be strictly needed for magnetic hardening of Cu-substrates, widening the range of organics of potential interest for enhancement of emergent magnetism at metal-organic interfaces.
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Affiliation(s)
- Lorena Martín-Olivera
- Stephenson
Institute for Renewable Energy, Department of Chemistry, The University of Liverpool, L69 3BX Liverpool, United Kingdom
| | - Dmitry G. Shchukin
- Stephenson
Institute for Renewable Energy, Department of Chemistry, The University of Liverpool, L69 3BX Liverpool, United Kingdom
| | - Gilberto Teobaldi
- Stephenson
Institute for Renewable Energy, Department of Chemistry, The University of Liverpool, L69 3BX Liverpool, United Kingdom
- Beijing
Computational Science Research Centre, Beijing 100193, China
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133
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Sun M, Wang X, Mi W. Spin polarization and magnetic characteristics at C6H6/Co2MnSi(001) spinterface. J Chem Phys 2017; 147:114702. [DOI: 10.1063/1.4996308] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Meifang Sun
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China
| | - Xiaocha Wang
- School of Electrical and Electronic Engineering, Tianjin University of Technology, Tianjin 300384,
China
| | - Wenbo Mi
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China
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134
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Mondal S, Maity S, Ghosh P. A Redox-Active Cascade Precursor: Isolation of a Zwitterionic Triphenylphosphonio-Hydrazyl Radical and an Indazolo-Indazole Derivative. Inorg Chem 2017; 56:8878-8888. [PMID: 28696110 DOI: 10.1021/acs.inorgchem.7b00818] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A redox-active [ML] unit (M = CoII and MnII; LH2 = N'-(1,4-dioxo-1,4-dihydronaphthalen-2-yl)benzohydrazide) defined as a cascade precursor that undergoes a multicomponent redox reaction comprising of a C-N bond formation, tautomerization, oxidation, C-C coupling, demetalation, and affording 6,14-dibenzoylbenzo[f]benzo[5,6]indazolo[3a,3-c]indazole-5,8,13,16-tetraone (IndL2) is reported. Conversion of LH2 → IndL2 in air is overall a (6H++6e) oxidation reaction, and it opens a route for the syntheses of bioactive diarylindazolo[3a,3-c]indazole derivatives. The reaction occurs via a radical coupling reaction, and the radical intermediate was isolated as a triphenylphosphonio adduct. In presence of PPh3 the [ML] unit promotes a reaction that involves a C-P bond formation, tautomerization, and oxidation to yield a stable zwitterionic triphenylphosphonio-hydrazyl radical (PPh3L±•). Conversion of LH2 → PPh3L±• is a (3H++3e) oxidation reaction. To authenticate the [ML] unit, in addition to the IndL2, a zinc(II) complex, [(L3)ZnII(H2O)Cl]·2MeOH (1·2MeOH), was successfully isolated (L3H = a pyridazine derivative of 1,4 naphthoquinone) from a reaction of LH2 with hydrated ZnCl2. Conversion of 3LH2 → 1 is also a multicomponent (6H++6e) oxidation reaction promoted by zinc(II) ion via a radical intermediate. Facile oxidation of [L2-] to [L•-] that was considered as an intermediate of these conversions was confirmed by isolating a 1,4 naphthoquinone-benzhydrazyl radical (LH•) complex, [(LH•)ZnII(H2O)Cl2] (2H•). The intermediates of LH2 → IndL2, LH2 → PPh3L±•, and 3LH2 → 1 conversions were analyzed by electrospray ionization mass spectroscopy. The molecular and electronic structures of PPh3L±•, IndL2, 1·2MeOH, and 2H• were confirmed by single-crystal X-ray crystallography, electron paramagnetic resonance spectroscopy, and density functional theory calculations.
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Affiliation(s)
- Sandip Mondal
- Department of Chemistry, R. K. Mission Residential College, Narendrapur , Kolkata 103, West Bengal, India
| | - Suvendu Maity
- Department of Chemistry, R. K. Mission Residential College, Narendrapur , Kolkata 103, West Bengal, India
| | - Prasanta Ghosh
- Department of Chemistry, R. K. Mission Residential College, Narendrapur , Kolkata 103, West Bengal, India
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135
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Mou Z, Kertesz M. Pancake Bond Orders of a Series of π‐Stacked Triangulene Radicals. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201704941] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Zhongyu Mou
- Chemistry Department Georgetown University 37th and O Streets, NW Washington DC 20057-1227 USA
| | - Miklos Kertesz
- Chemistry Department Georgetown University 37th and O Streets, NW Washington DC 20057-1227 USA
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136
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Mou Z, Kertesz M. Pancake Bond Orders of a Series of π‐Stacked Triangulene Radicals. Angew Chem Int Ed Engl 2017; 56:10188-10191. [DOI: 10.1002/anie.201704941] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Zhongyu Mou
- Chemistry Department Georgetown University 37th and O Streets, NW Washington DC 20057-1227 USA
| | - Miklos Kertesz
- Chemistry Department Georgetown University 37th and O Streets, NW Washington DC 20057-1227 USA
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137
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Mukherjee A, Sau SC, Mandal SK. Exploring Closed-Shell Cationic Phenalenyl: From Catalysis to Spin Electronics. Acc Chem Res 2017; 50:1679-1691. [PMID: 28665582 DOI: 10.1021/acs.accounts.7b00141] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The odd alternant hydrocarbon phenalenyl (PLY) can exist in three different forms, a closed-shell cation, an open-shell radical, and a closed-shell anion, using its nonbonding molecular orbital (NBMO). The chemistry of PLY-based molecules began more than five decades ago, and so far, the progress has mainly involved the open-shell neutral radical state. Over the last two decades, we have witnessed the evolution of a range of PLY-based radicals generating an array of multifunctional materials. However, it has been admitted that the practical applications of PLY radicals are greatly challenged by the low stability of the open-shell (radical) state. Recently, we took a different route to establish the utility of these PLY molecules using the closed-shell cationic state. In such a design, the closed-shell unit of PLY can readily accept free electrons, stabilizing in its NBMO upon generation of the open-shell state of the molecule. Thus, one can synthetically avoid the unstable open-shell state but still take advantage of this state by in situ generating the radical through external electron transfer or spin injection into the empty NBMO. It is worth noting that such approaches using closed-shell phenalenyl have been missing in the literature. This Account focuses on our recent developments using the closed-shell cationic state of the PLY molecule and its application in broad multidisciplinary areas spanning from catalysis to spin electronics. We describe how this concept has been utilized to develop a variety of homogeneous catalysts. For example, this concept was used in designing an iron(III) PLY-based electrocatalyst for a single-compartment H2O2 fuel cell, which delivered the best electrocatalytic activity among previously reported iron complexes, organometallic catalysts for various homogeneous organic transformations (hydroamination and polymerization), an organic Lewis acid catalyst for the ring opening of epoxides, and transition-metal-free C-H functionalization catalysts. Moreover, this concept of using the empty NBMO present in the closed-shell cationic state of the PLY moiety to capture electron(s) was further extended to an entirely different area of spin electronics to design a PLY-based spin-memory device, which worked by a spin-filtration mechanism using an organozinc compound based on a PLY backbone deposited over a ferromagnetic substrate. In this Account, we summarize our recent efforts to understand how this unexplored closed-shell state of the phenalenyl molecule, which has been known for over five decades, can be utilized in devising an array of materials that not only are important from an organometallic chemistry or organic chemistry point of view but also provide new understanding for device physics.
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Affiliation(s)
- Arup Mukherjee
- Department
of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts
Avenue, Cambridge, Massachusetts 02139, United States
| | - Samaresh Chandra Sau
- Department
of Chemical Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur 741246, India
| | - Swadhin K. Mandal
- Department
of Chemical Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur 741246, India
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138
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Tamblyn I. The electronic structure of nanoscale interfaces. MOLECULAR SIMULATION 2017. [DOI: 10.1080/08927022.2017.1313417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- I. Tamblyn
- National Research Council of Canada, Ottawa, Canada
- Department of Physics, University of Ontario Institute of Technology, Oshawa, Canada
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139
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Al Ma'Mari F, Rogers M, Alghamdi S, Moorsom T, Lee S, Prokscha T, Luetkens H, Valvidares M, Teobaldi G, Flokstra M, Stewart R, Gargiani P, Ali M, Burnell G, Hickey BJ, Cespedes O. Emergent magnetism at transition-metal-nanocarbon interfaces. Proc Natl Acad Sci U S A 2017; 114:5583-5588. [PMID: 28507160 PMCID: PMC5465901 DOI: 10.1073/pnas.1620216114] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Charge transfer at metallo-molecular interfaces may be used to design multifunctional hybrids with an emergent magnetization that may offer an eco-friendly and tunable alternative to conventional magnets and devices. Here, we investigate the origin of the magnetism arising at these interfaces by using different techniques to probe 3d and 5d metal films such as Sc, Mn, Cu, and Pt in contact with fullerenes and rf-sputtered carbon layers. These systems exhibit small anisotropy and coercivity together with a high Curie point. Low-energy muon spin spectroscopy in Cu and Sc-C60 multilayers show a quick spin depolarization and oscillations attributed to nonuniform local magnetic fields close to the metallo-carbon interface. The hybridization state of the carbon layers plays a crucial role, and we observe an increased magnetization as sp3 orbitals are annealed into sp2-π graphitic states in sputtered carbon/copper multilayers. X-ray magnetic circular dichroism (XMCD) measurements at the carbon K edge of C60 layers in contact with Sc films show spin polarization in the lowest unoccupied molecular orbital (LUMO) and higher π*-molecular levels, whereas the dichroism in the σ*-resonances is small or nonexistent. These results support the idea of an interaction mediated via charge transfer from the metal and dz-π hybridization. Thin-film carbon-based magnets may allow for the manipulation of spin ordering at metallic surfaces using electrooptical signals, with potential applications in computing, sensors, and other multifunctional magnetic devices.
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Affiliation(s)
- Fatma Al Ma'Mari
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
- Department of Physics, Sultan Qaboos University, 123 Muscat, Oman
| | - Matthew Rogers
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Shoug Alghamdi
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Timothy Moorsom
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Stephen Lee
- School of Physics and Astronomy, Scottish Universities Physics Alliance, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | - Thomas Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Hubertus Luetkens
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | | | - Gilberto Teobaldi
- Stephenson Institute for Renewable Energy, Department of Chemistry, University of Liverpool, Liverpool L69 3BX, United Kingdom
- Beijing Computational Science Research Centre, Beijing 100193 China
| | - Machiel Flokstra
- School of Physics and Astronomy, Scottish Universities Physics Alliance, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | - Rhea Stewart
- School of Physics and Astronomy, Scottish Universities Physics Alliance, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | | | - Mannan Ali
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Gavin Burnell
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - B J Hickey
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Oscar Cespedes
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom;
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140
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Fumanal M, Novoa JJ, Ribas-Arino J. Origin of Bistability in the Butyl-Substituted Spirobiphenalenyl-Based Neutral Radical Material. Chemistry 2017; 23:7772-7784. [DOI: 10.1002/chem.201700946] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Indexed: 01/24/2023]
Affiliation(s)
- Maria Fumanal
- Departament de Química Física and IQTCUB; Facultat de Química; Universitat de Barcelona; Av. Diagonal 645 08028 Barcelona Spain
- Current address: Laboratoire de Chimie Quantique; Institut de Chimie UMR7177; CNRS-Université de Strasbourg; 1 Rue Blaise Pascal BP 296/R8 67007 Strasbourg France
| | - Juan J. Novoa
- Departament de Química Física and IQTCUB; Facultat de Química; Universitat de Barcelona; Av. Diagonal 645 08028 Barcelona Spain
| | - Jordi Ribas-Arino
- Departament de Química Física and IQTCUB; Facultat de Química; Universitat de Barcelona; Av. Diagonal 645 08028 Barcelona Spain
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141
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Pavliček N, Mistry A, Majzik Z, Moll N, Meyer G, Fox DJ, Gross L. Synthesis and characterization of triangulene. NATURE NANOTECHNOLOGY 2017; 12:308-311. [PMID: 28192389 DOI: 10.1038/nnano.2016.305] [Citation(s) in RCA: 245] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 12/29/2016] [Indexed: 05/08/2023]
Abstract
Triangulene, the smallest triplet-ground-state polybenzenoid (also known as Clar's hydrocarbon), has been an enigmatic molecule ever since its existence was first hypothesized. Despite containing an even number of carbons (22, in six fused benzene rings), it is not possible to draw Kekulé-style resonant structures for the whole molecule: any attempt results in two unpaired valence electrons. Synthesis and characterization of unsubstituted triangulene has not been achieved because of its extreme reactivity, although the addition of substituents has allowed the stabilization and synthesis of the triangulene core and verification of the triplet ground state via electron paramagnetic resonance measurements. Here we show the on-surface generation of unsubstituted triangulene that consists of six fused benzene rings. The tip of a combined scanning tunnelling and atomic force microscope (STM/AFM) was used to dehydrogenate precursor molecules. STM measurements in combination with density functional theory (DFT) calculations confirmed that triangulene keeps its free-molecule properties on the surface, whereas AFM measurements resolved its planar, threefold symmetric molecular structure. The unique topology of such non-Kekulé hydrocarbons results in open-shell π-conjugated graphene fragments that give rise to high-spin ground states, potentially useful in organic spintronic devices. Our generation method renders manifold experiments possible to investigate triangulene and related open-shell fragments at the single-molecule level.
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Affiliation(s)
| | - Anish Mistry
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Zsolt Majzik
- IBM Research-Zurich, 8803 Rüschlikon, Switzerland
| | - Nikolaj Moll
- IBM Research-Zurich, 8803 Rüschlikon, Switzerland
| | | | - David J Fox
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Leo Gross
- IBM Research-Zurich, 8803 Rüschlikon, Switzerland
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142
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Cinchetti M, Dediu VA, Hueso LE. Activating the molecular spinterface. NATURE MATERIALS 2017; 16:507-515. [PMID: 28439116 DOI: 10.1038/nmat4902] [Citation(s) in RCA: 140] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 03/23/2017] [Indexed: 05/19/2023]
Abstract
The miniaturization trend in the semiconductor industry has led to the understanding that interfacial properties are crucial for device behaviour. Spintronics has not been alien to this trend, and phenomena such as preferential spin tunnelling, the spin-to-charge conversion due to the Rashba-Edelstein effect and the spin-momentum locking at the surface of topological insulators have arisen mainly from emergent interfacial properties, rather than the bulk of the constituent materials. In this Perspective we explore inorganic/molecular interfaces by looking closely at both sides of the interface. We describe recent developments and discuss the interface as an ideal platform for creating new spin effects. Finally, we outline possible technologies that can be generated thanks to the unique active tunability of molecular spinterfaces.
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Affiliation(s)
- Mirko Cinchetti
- Experimentelle Physik VI, Technische Universität Dortmund, 44221 Dortmund, Germany
| | - V Alek Dediu
- Istituto per lo Studio dei Materiali Nanostrutturati CNRISMN, 40129 Bologna, Italy
| | - Luis E Hueso
- CIC nanoGUNE, 20018 San Sebastian, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
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143
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Jasper-Tönnies T, Gruber M, Karan S, Jacob H, Tuczek F, Berndt R. Deposition of a Cationic Fe III Spin-Crossover Complex on Au(111): Impact of the Counter Ion. J Phys Chem Lett 2017; 8:1569-1573. [PMID: 28319403 DOI: 10.1021/acs.jpclett.7b00457] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Spin-crossover molecules on metallic substrates have recently attracted considerable interest for their potential applications in molecular spintronics. Using scanning tunneling microscopy, we evidence the first successful deposition of a charged FeIII spin-crossover complex, [Fe(pap)2]+ (pap = N-2-pyridylmethylidene-2-hydroxyphenylaminato), on Au(111). Furthermore, the bulk form of the molecules is stabilized by a perchlorate counterion, which depending on the deposition technique may affect the quality of the deposition and the measurements. Finally, we evidence switching of the molecules on Au(111).
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Affiliation(s)
- Torben Jasper-Tönnies
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , 24098 Kiel, Germany
| | - Manuel Gruber
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , 24098 Kiel, Germany
| | - Sujoy Karan
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , 24098 Kiel, Germany
| | - Hanne Jacob
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel , 24098 Kiel, Germany
| | - Felix Tuczek
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel , 24098 Kiel, Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , 24098 Kiel, Germany
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144
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Gruber M, Miyamachi T, Davesne V, Bowen M, Boukari S, Wulfhekel W, Alouani M, Beaurepaire E. Spin crossover in Fe(phen)2(NCS)2 complexes on metallic surfaces. J Chem Phys 2017. [DOI: 10.1063/1.4973511] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Manuel Gruber
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Toshio Miyamachi
- The Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwa 277-8581, Japan
| | - Vincent Davesne
- Laboratoire de Chimie de Coordination, 205 Route de Narbonne, 31077 Cedex 04 Toulouse, France
| | - Martin Bowen
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504, 23 Rue du Loess, BP 43, 67034 Cedex 2 Strasbourg, France
| | - Samy Boukari
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504, 23 Rue du Loess, BP 43, 67034 Cedex 2 Strasbourg, France
| | - Wulf Wulfhekel
- Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, 76131 Karlsruhe, Germany
| | - Mebarek Alouani
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504, 23 Rue du Loess, BP 43, 67034 Cedex 2 Strasbourg, France
| | - Eric Beaurepaire
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504, 23 Rue du Loess, BP 43, 67034 Cedex 2 Strasbourg, France
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145
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Atxabal A, Ribeiro M, Parui S, Urreta L, Sagasta E, Sun X, Llopis R, Casanova F, Hueso LE. Spin doping using transition metal phthalocyanine molecules. Nat Commun 2016; 7:13751. [PMID: 27941810 PMCID: PMC5159905 DOI: 10.1038/ncomms13751] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 10/31/2016] [Indexed: 11/24/2022] Open
Abstract
Molecular spins have become key enablers for exploring magnetic interactions, quantum information processes and many-body effects in metals. Metal-organic molecules, in particular, let the spin state of the core metal ion to be modified according to its organic environment, allowing localized magnetic moments to emerge as functional entities with radically different properties from its simple atomic counterparts. Here, using and preserving the integrity of transition metal phthalocyanine high-spin complexes, we demonstrate the magnetic doping of gold thin films, effectively creating a new ground state. We demonstrate it by electrical transport measurements that are sensitive to the scattering of itinerant electrons with magnetic impurities, such as Kondo effect and weak antilocalization. Our work expands in a simple and powerful way the classes of materials that can be used as magnetic dopants, opening a new channel to couple the wide range of molecular properties with spin phenomena at a functional scale.
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Affiliation(s)
- A. Atxabal
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
| | - M. Ribeiro
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
| | - S. Parui
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
| | - L. Urreta
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
| | - E. Sagasta
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
| | - X. Sun
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
- CAS Center for Excellence in Nanoscience, Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
| | - R. Llopis
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
| | - F. Casanova
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
- IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
| | - L. E. Hueso
- CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain
- IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
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146
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Wang K, Strambini E, Sanderink JGM, Bolhuis T, van der Wiel WG, de Jong MP. Effect of Orbital Hybridization on Spin-Polarized Tunneling across Co/C 60 Interfaces. ACS APPLIED MATERIALS & INTERFACES 2016; 8:28349-28356. [PMID: 27624282 DOI: 10.1021/acsami.6b08313] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The interaction between ferromagnetic surfaces and organic semiconductors leads to the formation of hybrid interfacial states. As a consequence, the local magnetic moment is altered, a hybrid interfacial density of states (DOS) is formed, and spin-dependent shifts of energy levels occur. Here, we show that this hybridization affects spin transport across the interface significantly. We report spin-dependent electronic transport measurements for tunnel junctions comprising C60 molecular thin films grown on top of face-centered-cubic (fcc) epitaxial Co electrodes, an AlOx tunnel barrier, and an Al counter electrode. Since only one ferromagnetic electrode (Co) is present, spin-polarized transport is due to tunneling anisotropic magnetoresistance (TAMR). An in-plane TAMR ratio of approximately 0.7% has been measured at 5 K under application of a magnetic field of 800 mT. The magnetic switching behavior shows some remarkable features, which are attributed to the rotation of interfacial magnetic moments. This behavior can be ascribed to the magnetic coupling between the Co thin films and the newly formed Co/C60 hybridized interfacial states. Using the Tedrow-Meservey technique, the tunnel spin polarization of the Co/C60 interface was found to be 43%.
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Affiliation(s)
- Kai Wang
- NanoElectronics (NE) Group, MESA+ Institute for Nanotechnology, University of Twente , P. O. Box 217, Enschede 7500AE, The Netherlands
| | - Elia Strambini
- NanoElectronics (NE) Group, MESA+ Institute for Nanotechnology, University of Twente , P. O. Box 217, Enschede 7500AE, The Netherlands
| | - Johnny G M Sanderink
- NanoElectronics (NE) Group, MESA+ Institute for Nanotechnology, University of Twente , P. O. Box 217, Enschede 7500AE, The Netherlands
| | - Thijs Bolhuis
- NanoElectronics (NE) Group, MESA+ Institute for Nanotechnology, University of Twente , P. O. Box 217, Enschede 7500AE, The Netherlands
| | - Wilfred G van der Wiel
- NanoElectronics (NE) Group, MESA+ Institute for Nanotechnology, University of Twente , P. O. Box 217, Enschede 7500AE, The Netherlands
| | - Michel P de Jong
- NanoElectronics (NE) Group, MESA+ Institute for Nanotechnology, University of Twente , P. O. Box 217, Enschede 7500AE, The Netherlands
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147
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Behnia S, Fathizadeh S, Akhshani A. Modeling spin selectivity in charge transfer across the DNA/Gold interface. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2016.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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148
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Droghetti A, Thielen P, Rungger I, Haag N, Großmann N, Stöckl J, Stadtmüller B, Aeschlimann M, Sanvito S, Cinchetti M. Dynamic spin filtering at the Co/Alq3 interface mediated by weakly coupled second layer molecules. Nat Commun 2016; 7:12668. [PMID: 27578395 PMCID: PMC5013676 DOI: 10.1038/ncomms12668] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 07/21/2016] [Indexed: 11/09/2022] Open
Abstract
Spin filtering at organic-metal interfaces is often determined by the details of the interaction between the organic molecules and the inorganic magnets used as electrodes. Here we demonstrate a spin-filtering mechanism based on the dynamical spin relaxation of the long-living interface states formed by the magnet and weakly physisorbed molecules. We investigate the case of Alq3 on Co and, by combining two-photon photoemission experiments with electronic structure theory, show that the observed long-time spin-dependent electron dynamics is driven by molecules in the second organic layer. The interface states formed by physisorbed molecules are not spin-split, but acquire a spin-dependent lifetime, that is the result of dynamical spin-relaxation driven by the interaction with the Co substrate. Such spin-filtering mechanism has an important role in the injection of spin-polarized carriers across the interface and their successive hopping diffusion into successive molecular layers of molecular spintronics devices.
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Affiliation(s)
- Andrea Droghetti
- School of Physics, AMBER and CRANN Institute, Trinity College, Dublin 2, Ireland.,Nano-Bio Spectroscopy Group and European Theoretical Spectroscopy Facility (ETSF), Universidad del Pais Vasco CFM, CSIC-UPV/EHU-MPC &DIPC, Avenue Tolosa 72, 20018 San Sebastian, Spain
| | - Philip Thielen
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Erwin-Schroedinger Strasse 46, 67663 Kaiserslautern, Germany.,Graduate School of Excellence Materials Science in Mainz, Gottlieb-Daimler-Strasse 47, 67663 Kaiserslautern, Germany
| | - Ivan Rungger
- School of Physics, AMBER and CRANN Institute, Trinity College, Dublin 2, Ireland.,National Physical Laboratory, Teddington TW11 0LW, UK
| | - Norman Haag
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Erwin-Schroedinger Strasse 46, 67663 Kaiserslautern, Germany
| | - Nicolas Großmann
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Erwin-Schroedinger Strasse 46, 67663 Kaiserslautern, Germany
| | - Johannes Stöckl
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Erwin-Schroedinger Strasse 46, 67663 Kaiserslautern, Germany
| | - Benjamin Stadtmüller
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Erwin-Schroedinger Strasse 46, 67663 Kaiserslautern, Germany.,Graduate School of Excellence Materials Science in Mainz, Gottlieb-Daimler-Strasse 47, 67663 Kaiserslautern, Germany
| | - Martin Aeschlimann
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Erwin-Schroedinger Strasse 46, 67663 Kaiserslautern, Germany
| | - Stefano Sanvito
- School of Physics, AMBER and CRANN Institute, Trinity College, Dublin 2, Ireland
| | - Mirko Cinchetti
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Erwin-Schroedinger Strasse 46, 67663 Kaiserslautern, Germany
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149
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Lan Y, Magri A, Fuhr O, Ruben M. Phenalenyl-based mononuclear dysprosium complexes. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2016; 7:995-1009. [PMID: 27547617 PMCID: PMC4979880 DOI: 10.3762/bjnano.7.92] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 06/24/2016] [Indexed: 06/06/2023]
Abstract
The phenalenyl-based dysprosium complexes [Dy(PLN)2(HPLN)Cl(EtOH)] (1), [Dy(PLN)3(HPLN)]·[Dy(PLN)3(EtOH)]·2EtOH (2) and [Dy(PLN)3(H2O)2]·H2O (3), HPLN being 9-hydroxy-1H-phenalen-1-one, have been synthesized. All compounds were fully characterized by means of single crystal X-ray analysis, paramagnetic (1)H NMR, MALDI-TOF mass spectrometry, UV-vis spectrophotometry and magnetic measurements. Both static (dc) and dynamic (ac) magnetic properties of these complexes have been investigated, showing slow relaxation of magnetization, indicative of single molecule magnet (SMM) behavior. Attempts to synthesize sublimable phenalenyl-based dysprosium complexes have been made by implementing a synthetic strategy under anhydrous conditions. The sublimed species were characterized and their thermal stability was confirmed. This opens up the possibility to deposit phenalenyl-based lanthanides complexes by sublimation onto surfaces, an important prerequisite for ongoing studies in molecular spintronics.
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Affiliation(s)
- Yanhua Lan
- Institut für Nanotechnologie, Karlsruher Institut für Technologie (KIT), Postfach 3640, D-76344 Karlsruhe, Germany (Tel: +49 721-608-28948)
- Institut Néel, CNRS, Nanosciences Department, BP 166, 25 rue des Martyrs, 38042 GRENOBLE Cedex 9, France
| | - Andrea Magri
- Institut für Nanotechnologie, Karlsruher Institut für Technologie (KIT), Postfach 3640, D-76344 Karlsruhe, Germany (Tel: +49 721-608-28948)
| | - Olaf Fuhr
- Institut für Nanotechnologie, Karlsruher Institut für Technologie (KIT), Postfach 3640, D-76344 Karlsruhe, Germany (Tel: +49 721-608-28948)
- Karlsruhe Nano Micro Facility (KNMF), Karlsruher Institut für Technologie (KIT), Postfach 3640, D-76344 Karlsruhe, Germany
| | - Mario Ruben
- Institut für Nanotechnologie, Karlsruher Institut für Technologie (KIT), Postfach 3640, D-76344 Karlsruhe, Germany (Tel: +49 721-608-28948)
- Université de Strasbourg, Institut de Physique et de Chimie des Materiaux de Strasbourg, Campus de Cronenbourg, 23 Rue du Loess, 67034 Strasbourg Cedex 2, France
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150
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Djeghloul F, Gruber M, Urbain E, Xenioti D, Joly L, Boukari S, Arabski J, Bulou H, Scheurer F, Bertran F, Le Fèvre P, Taleb-Ibrahimi A, Wulfhekel W, Garreau G, Hajjar-Garreau S, Wetzel P, Alouani M, Beaurepaire E, Bowen M, Weber W. High Spin Polarization at Ferromagnetic Metal-Organic Interfaces: A Generic Property. J Phys Chem Lett 2016; 7:2310-2315. [PMID: 27266579 DOI: 10.1021/acs.jpclett.6b01112] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A high spin polarization of states around the Fermi level, EF, at room temperature has been measured in the past at the interface between a few molecular candidates and the ferromagnetic metal Co. Is this promising property for spintronics limited to these candidates? Previous reports suggested that certain conditions, such as strong ferromagnetism, i.e., a fully occupied spin-up d band of the ferromagnet, or the presence of π bonds on the molecule, i.e., molecular conjugation, needed to be met. What rules govern the presence of this property? We have performed spin-resolved photoemission spectroscopy measurements on a variety of such interfaces. We find that this property is robust against changes to the molecule and ferromagnetic metal's electronic properties, including the aforementioned conditions. This affirms the generality of highly spin-polarized states at the interface between a ferromagnetic metal and a molecule and augurs bright prospects toward integrating these interfaces within organic spintronic devices.
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Affiliation(s)
- Fatima Djeghloul
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Manuel Gruber
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
- Physikalisches Institut, Karlsruhe Institute of Technology , Wolfgang-Gaede-Strasse 1, 76131 Karlsruhe, Germany
| | - Etienne Urbain
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Dimitra Xenioti
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Loic Joly
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Samy Boukari
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Jacek Arabski
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Hervé Bulou
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Fabrice Scheurer
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - François Bertran
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette, France
| | - Patrick Le Fèvre
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette, France
| | - Amina Taleb-Ibrahimi
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette, France
| | - Wulf Wulfhekel
- Physikalisches Institut, Karlsruhe Institute of Technology , Wolfgang-Gaede-Strasse 1, 76131 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology , 76021 Karlsruhe, Germany
| | - Guillaume Garreau
- Institut de Science des Matériaux de Mulhouse, CNRS-UMR 7361, Université de Haute-Alsace , 68057 Mulhouse, France
| | - Samar Hajjar-Garreau
- Institut de Science des Matériaux de Mulhouse, CNRS-UMR 7361, Université de Haute-Alsace , 68057 Mulhouse, France
| | - Patrick Wetzel
- Institut de Science des Matériaux de Mulhouse, CNRS-UMR 7361, Université de Haute-Alsace , 68057 Mulhouse, France
| | - Mebarek Alouani
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Eric Beaurepaire
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Martin Bowen
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
| | - Wolfgang Weber
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS UMR 7504 , 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France
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