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Manipulating the Magnetic and Electrical Properties of Strongly Correlated Molecular Crystals.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Manipulating the Magnetic and Electrical Properties of Strongly Correlated Molecular Crystals./
作者:	Hu, Yong.
面頁冊數:	1 online resource (184 pages)
附註:	Source: Dissertations Abstracts International, Volume: 83-12, Section: B.
Contained By:	Dissertations Abstracts International83-12B.
標題:	Mechanical engineering. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29170148click for full text (PQDT)
ISBN:	9798834000891

Manipulating the Magnetic and Electrical Properties of Strongly Correlated Molecular Crystals.
Hu, Yong.

Manipulating the Magnetic and Electrical Properties of Strongly Correlated Molecular Crystals. - 1 online resource (184 pages)

Source: Dissertations Abstracts International, Volume: 83-12, Section: B.

Thesis (Ph.D.)--State University of New York at Buffalo, 2022.

Includes bibliographical references

Strongly correlated materials refer to materials whose electronic properties are determined by strong electron-electron interactions, such as electron-electron coulomb interaction. In strongly correlated molecular crystals, the coupling of charge, spin, and orbital is driven by electron-electron interaction to generate abundant electronically ordered phases, such as magnetic, ferroelectric, and electrically conductive phases. These phases show very sensitive responses to external stimuli, making them promising for potential application in memory, sensor, and quantum information.This dissertation reports the manipulation of magnetic and electrical properties in strongly correlated molecular crystals. Molecular crystal, potassium-7,7,8,8-tetracyanoquinodimethan (K-TCNQ) is studied. K-TCNQ is selected since it is a quasi-1D molecular crystal with spin-Peierls transition. The strong electron-phonon coupling results in a diamagnetic low-conductive phase at room temperature. My study shows that an electric field of 17 kV cm-1 can be applied to induce dielectric breakdown in K-TCNQ which results in a reversible phase transition from the diamagnetic low-conductive phase (7 μΩ-1 cm-1) to a paramagnetic high-conductive phase (443 μΩ-1 cm-1) at room temperature. The phase transition is reversed when the electric field is removed. The electric-field induced magnetic and electrical phase transition shows excellent cycling stability of over 105 cycles at room temperature. Mechanism studies by electron spin resonance and low-frequency noise measurements show that the electric-field induced high-conductive phase is an electronically inhomogeneous state, including both high-conductive and low-conductive areas. Only electronic structure change is observed in the transition. After demonstrating the reversible electric-field induced magnetic and electrical phase transition in K-TCNQ. I further study the possibility to maintain the paramagnetic high-conductive state of K-TCNQ at room temperature. I use the high-power pulsed optical excitation (8 ns pulsed laser, 532 nm, 15 MW cm-2) as the tool, which can provide both photoexcitation and a high strain-rate effect, to realize a statable paramagnetic high-conductive phase. A high-conductive phase of about 42 Ωcm, about four orders of magnitude lower than that of the low-conductive phase, is obtained and the stability test shows the acquired phase is stable for more than 400 days. In addition, magnetic and electrical bistability (two stable equilibrium states, a stable paramagnetic high-conductive and a stable diamagnetic low-conductive state) is also demonstrated in a broad temperature range (2 to 360 K). Mechanism study based on noise spectroscopy, electron spin resonance, theoretical calculation, and scanning tunneling microscopy and spectroscopy show that the stable paramagnetic high-conductive phase is an electronic inhomogeneous phase and requires fine control over spin-charge-lattice coupling.The magnetic and electrical bistability is achieved in a paramagnetic molecular crystal (K-TCNQ). I further study the manipulation of magnetic properties in high Curie temperature (317 K) molecule-based magnets (V[Cr(CN)6]0.85·1.74H2O), which are assembled by organic ligands and metal ions. V[Cr(CN)6]0.85·1.74H2O is selected due to its structural vacancy which allows mass transfer (such as proton and alkali metal ions), promising the control of magnetism by ion insertion and extraction. Lithiation/delithiation in a lithium-ion battery (1 M Li+) is adopted for the reversible magnetic order switching between ferrimagnetic to paramagnetic phase in the molecule-based magnet. Theoretical calculation shows that the water network, formed by the ligand and zeolitic water molecules through hydrogen bonds, is broken in V[Cr(CN)6]0.85·1.74H2O after lithium-ion intercalation. Fourier-transform infrared spectroscopy and electrochemical study show that magnetic order switching is realized through the redox reaction of transition metal ions (V2+/V3+). Based on the obtained lithium-ion control of molecule-based magnetism, I simulate and design the microwave-activated sensor for the state-of-charge estimation in lithium battery, which is a challenge in the rechargeable battery application. The state-of-charge estimation for lithium-ion battery is detected through the ferromagnetic resonance which can reveal the extent of Li+ insertion/extraction in V[Cr(CN)6]0.85·1.74H2O. My study shows that the sensor based on the molecule-based magnet can be activated with microwave radiation at a low frequency of 0.35 GHz and has a magnetic field of 100 Oe. I further explore a stable way for the magnetism control on the molecule-based magnet through proton-mediated magnetoelectric coupling. A water-soluble molecular ferroelectric candidate, imidazolium perchlorate, is selected from machine learning. The heterogeneous composite of molecular ferroelectrics and a molecule-based magnet is obtained through hydrogel-based additive manufacturing. The obtained molecule-based magnetoelectric composite show 29% magnetization change along with a broad thermal hysteresis width of 160 K. The magnetic order control is demonstrated in a low electric field of 1 kV cm-1 through proton-mediated magnetoelectric coupling (coupling between magnetic and the electric properties).

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2023

Mode of access: World Wide Web

ISBN: 9798834000891Subjects--Topical Terms:

649730
Mechanical engineering.
Subjects--Index Terms:

Magneto-ionicIndex Terms--Genre/Form:

542853
Electronic books.

Manipulating the Magnetic and Electrical Properties of Strongly Correlated Molecular Crystals.
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504 $a Includes bibliographical references
520 $a Strongly correlated materials refer to materials whose electronic properties are determined by strong electron-electron interactions, such as electron-electron coulomb interaction. In strongly correlated molecular crystals, the coupling of charge, spin, and orbital is driven by electron-electron interaction to generate abundant electronically ordered phases, such as magnetic, ferroelectric, and electrically conductive phases. These phases show very sensitive responses to external stimuli, making them promising for potential application in memory, sensor, and quantum information.This dissertation reports the manipulation of magnetic and electrical properties in strongly correlated molecular crystals. Molecular crystal, potassium-7,7,8,8-tetracyanoquinodimethan (K-TCNQ) is studied. K-TCNQ is selected since it is a quasi-1D molecular crystal with spin-Peierls transition. The strong electron-phonon coupling results in a diamagnetic low-conductive phase at room temperature. My study shows that an electric field of 17 kV cm-1 can be applied to induce dielectric breakdown in K-TCNQ which results in a reversible phase transition from the diamagnetic low-conductive phase (7 μΩ-1 cm-1) to a paramagnetic high-conductive phase (443 μΩ-1 cm-1) at room temperature. The phase transition is reversed when the electric field is removed. The electric-field induced magnetic and electrical phase transition shows excellent cycling stability of over 105 cycles at room temperature. Mechanism studies by electron spin resonance and low-frequency noise measurements show that the electric-field induced high-conductive phase is an electronically inhomogeneous state, including both high-conductive and low-conductive areas. Only electronic structure change is observed in the transition. After demonstrating the reversible electric-field induced magnetic and electrical phase transition in K-TCNQ. I further study the possibility to maintain the paramagnetic high-conductive state of K-TCNQ at room temperature. I use the high-power pulsed optical excitation (8 ns pulsed laser, 532 nm, 15 MW cm-2) as the tool, which can provide both photoexcitation and a high strain-rate effect, to realize a statable paramagnetic high-conductive phase. A high-conductive phase of about 42 Ωcm, about four orders of magnitude lower than that of the low-conductive phase, is obtained and the stability test shows the acquired phase is stable for more than 400 days. In addition, magnetic and electrical bistability (two stable equilibrium states, a stable paramagnetic high-conductive and a stable diamagnetic low-conductive state) is also demonstrated in a broad temperature range (2 to 360 K). Mechanism study based on noise spectroscopy, electron spin resonance, theoretical calculation, and scanning tunneling microscopy and spectroscopy show that the stable paramagnetic high-conductive phase is an electronic inhomogeneous phase and requires fine control over spin-charge-lattice coupling.The magnetic and electrical bistability is achieved in a paramagnetic molecular crystal (K-TCNQ). I further study the manipulation of magnetic properties in high Curie temperature (317 K) molecule-based magnets (V[Cr(CN)6]0.85·1.74H2O), which are assembled by organic ligands and metal ions. V[Cr(CN)6]0.85·1.74H2O is selected due to its structural vacancy which allows mass transfer (such as proton and alkali metal ions), promising the control of magnetism by ion insertion and extraction. Lithiation/delithiation in a lithium-ion battery (1 M Li+) is adopted for the reversible magnetic order switching between ferrimagnetic to paramagnetic phase in the molecule-based magnet. Theoretical calculation shows that the water network, formed by the ligand and zeolitic water molecules through hydrogen bonds, is broken in V[Cr(CN)6]0.85·1.74H2O after lithium-ion intercalation. Fourier-transform infrared spectroscopy and electrochemical study show that magnetic order switching is realized through the redox reaction of transition metal ions (V2+/V3+). Based on the obtained lithium-ion control of molecule-based magnetism, I simulate and design the microwave-activated sensor for the state-of-charge estimation in lithium battery, which is a challenge in the rechargeable battery application. The state-of-charge estimation for lithium-ion battery is detected through the ferromagnetic resonance which can reveal the extent of Li+ insertion/extraction in V[Cr(CN)6]0.85·1.74H2O. My study shows that the sensor based on the molecule-based magnet can be activated with microwave radiation at a low frequency of 0.35 GHz and has a magnetic field of 100 Oe. I further explore a stable way for the magnetism control on the molecule-based magnet through proton-mediated magnetoelectric coupling. A water-soluble molecular ferroelectric candidate, imidazolium perchlorate, is selected from machine learning. The heterogeneous composite of molecular ferroelectrics and a molecule-based magnet is obtained through hydrogel-based additive manufacturing. The obtained molecule-based magnetoelectric composite show 29% magnetization change along with a broad thermal hysteresis width of 160 K. The magnetic order control is demonstrated in a low electric field of 1 kV cm-1 through proton-mediated magnetoelectric coupling (coupling between magnetic and the electric properties).
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2023
538 $a Mode of access: World Wide Web
650 4 $a Mechanical engineering. $3 649730
653 $a Magneto-ionic
653 $a Magnetoelectricity
653 $a Molecular Ferroelectrics
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653 $a Organic conductor
653 $a Strongly correlated material
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710 2 $a ProQuest Information and Learning Co. $3 783688
710 2 $a State University of New York at Buffalo. $b Mechanical and Aerospace Engineering. $3 1017747
773 0 $t Dissertations Abstracts International $g 83-12B.
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29170148 $z click for full text (PQDT)