scholarly journals AC Susceptibility Studies of Magnetic Relaxation in Mn12-Stearate SMMs on the Spherical Silica Surface

2021 ◽  
Vol 7 (9) ◽  
pp. 122
Author(s):  
Oleksandr Pastukh ◽  
Piotr Konieczny ◽  
Magdalena Laskowska ◽  
Łukasz Laskowski
Keyword(s):  
Single Molecule ◽  
Silica Surface ◽  
Ac Susceptibility ◽  
Relaxation Times ◽  
Single Molecule Magnets ◽  
Relaxation Parameters ◽  
Spherical Silica ◽  
Measuring Techniques ◽  
Different Temperatures ◽  
Nanostructured Silica

The study of magnetic relaxations in Mn12-stearate single-molecule magnets deposited on the surface of spherical silica nanoparticles was performed. For such a purpose, the investigation of AC magnetic susceptibility dependence on the frequency and temperature was performed. Based on the Argand plots obtained for different temperatures and temperature dependencies of susceptibility, obtained for different frequencies of AC field, the corresponding relaxation times were derived. Fitting to the Arrhenius law revealed the values of an effective energy barrier and a mean relaxation time, which were consistent for both measuring techniques (Ueff/kB∼ 50 K and τ0∼ 10−7 s) and similar to the corresponding values for the analogous bulk compounds. Additionally, the obtained relaxation parameters for the Mn12-stearate molecules on the spherical silica surface were compared with corresponding values for the Mn12-based single-molecule magnets deposited upon other types of nanostructured silica surface.

scholarly journals Uncertainty Estimates for Magnetic Relaxation Times and Magnetic Relaxation Parameters

2019 ◽  
Author(s):  
Daniel Reta ◽  
Nicholas Chilton
Keyword(s):  
Single Molecule ◽  
Magnetic Relaxation ◽  
High Performance ◽  
Ac Susceptibility ◽  
Relaxation Times ◽  
Model Parameters ◽  
Single Molecule Magnets ◽  
Relaxation Parameters ◽  
Uncertainty Estimates ◽  
Crystallographic Disorder

We describe a method for obtaining uncertainties in magnetic relaxation times from AC susceptibility experiments. We provide a program for fitting AC data and the resulting magnetic relaxation times accounting for the uncertainties correctly, to give magnetic relaxation parameters with accurate uncertainties. We show that the implicit distributions in the magnetic relaxation times have large consequences for the uncertainties in the model parameters, and that the magnitude of these uncertainties appear to correlate with crystallographic disorder in three families of high-performance Dy(III) single-molecule magnets.

scholarly journals Uncertainty Estimates for Magnetic Relaxation Times and Magnetic Relaxation Parameters

2019 ◽  
Author(s):  
Daniel Reta ◽  
Nicholas Chilton
Keyword(s):  
Single Molecule ◽  
Magnetic Relaxation ◽  
High Performance ◽  
Ac Susceptibility ◽  
Relaxation Times ◽  
Model Parameters ◽  
Single Molecule Magnets ◽  
Relaxation Parameters ◽  
Uncertainty Estimates ◽  
Crystallographic Disorder

We describe a method for obtaining uncertainties in magnetic relaxation times from AC susceptibility experiments. We provide a program for fitting AC data and the resulting magnetic relaxation times accounting for the uncertainties correctly, to give magnetic relaxation parameters with accurate uncertainties. We show that the implicit distributions in the magnetic relaxation times have large consequences for the uncertainties in the model parameters, and that the magnitude of these uncertainties appear to correlate with crystallographic disorder in three families of high-performance Dy(III) single-molecule magnets.

scholarly journals Magnetic Behaviour of Mn12-Stearate Single-Molecule Magnets Immobilized on the Surface of 300 nm Spherical Silica Nanoparticles

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2624 ◽  
Author(s):  
Magdalena Laskowska ◽  
Oleksandr Pastukh ◽  
Piotr Konieczny ◽  
Mateusz Dulski ◽  
Marcin Zalsiński ◽  
...  
Keyword(s):  
Silica Nanoparticles ◽  
Single Molecule ◽  
Silica Surface ◽  
Magnetic Measurements ◽  
Magnetic Behaviour ◽  
Silica Spheres ◽  
Squid Magnetometry ◽  
Single Molecule Magnets ◽  
Transmission Electron ◽  
Spherical Silica

The magnetic behaviour of Mn 12 -stearate single-molecule magnets (SMMs) ([ Mn 12 O 12 ( CH 3 ( CH 2 ) 16 CO 2 ) 16 ] · 2 CH 3 COOH · 4 H 2 O ) on the surface of 300 nm spherical silica nanoparticles were investigated. The SMMs were bonded at the silica surface with the assumed number of anchoring points, which influenced on their degree of freedom and distribution. In order to check the properties of Mn 12 -stearate molecules separated on the silica surface, and check their interactions, the samples containing four different concentration of spacers per single anchoring unit and variously bonded Mn 12 -stearate particles were prepared. The materials have been examined using Raman spectroscopy, transmission electron microscopy, and SQUID magnetometry. The results of magnetic measurements showed a correlation between the way of single-molecule magnets immobilization onto the silica spheres and the magnetic properties of the obtained hybrid materials.

scholarly journals Leveraging Surface Siloxide Electronics to Enhance Relaxation Properties of a Single-Molecule Magnet

2020 ◽  
Author(s):  
Maciej Korzynski ◽  
Zachariah Berkson ◽  
Boris Le Guennic ◽  
Olivier Cador ◽  
Christophe Copéret
Keyword(s):  
Single Molecule ◽  
Relaxation Times ◽  
Device Fabrication ◽  
Information Storage ◽  
Commercial Application ◽  
Surface Immobilization ◽  
Single Molecule Magnets ◽  
Magnetization Relaxation ◽  
Surface Deposition ◽  
Magnitude Increase

Single-molecule magnets (SMMs) hold promise for unmatched information storage density as well as applications in quantum computing and spintronics. To date, the most successful SMMs are organometallic lanthanide complexes. However, their surface immobilization, one of the requirements for device fabrication and commercial application, remains challenging due to sensitivity of magnetic properties to small changes in the electronic structure of the parent SMM. Thus, finding controlled approaches to SMM surface deposition is a timely challenge. In this contribution we apply the concept of isolobality to identify siloxides present at the surface of partially dehydroxylated silica as a suitable replacement for archetypal ligand architectures in organometallic SMMs. We demonstrate theoretically and experimentally that isolated siloxide anchorages not only enable successful immobilization, but also lead to two-orders-of-magnitude increase in magnetization relaxation times and provide magnetic site dilution.

Spin dynamics in two ReF6 -based single-molecule magnets from NMR and ac susceptibility measurements

2020 ◽  
Vol 101 (13) ◽  
Author(s):  
Oleg M. Vyaselev ◽  
Nataliya D. Kushch ◽  
Eduard B. Yagubskii ◽  
Olga V. Maximova ◽  
Alexander N. Vasiliev
Keyword(s):  
Single Molecule ◽  
Spin Dynamics ◽  
Ac Susceptibility ◽  
Single Molecule Magnets

Single-Molecule Magnets: Characterization of Complexes Exhibiting Out-of-Phase AC Susceptibility Signals

1997 ◽  
Vol 305 (1) ◽  
pp. 167-179 ◽  
Author(s):  
Hilary J. Eppley ◽  
Sheila M. J. Aubin ◽  
Michael W. Wemple ◽  
David M. Adams ◽  
Hui-Lien Tsai ◽  
...  
Keyword(s):  
Single Molecule ◽  
Ac Susceptibility ◽  
Single Molecule Magnets

scholarly journals Leveraging Surface Siloxide Electronics to Enhance Relaxation Properties of a Single-Molecule Magnet

2021 ◽  
Author(s):  
Maciej Korzynski ◽  
Zachariah Berkson ◽  
Boris Le Guennic ◽  
Olivier Cador ◽  
Christophe Copéret
Keyword(s):  
Single Molecule ◽  
Relaxation Times ◽  
Device Fabrication ◽  
Information Storage ◽  
Commercial Application ◽  
Surface Immobilization ◽  
Single Molecule Magnets ◽  
Magnetization Relaxation ◽  
Surface Deposition ◽  
Magnitude Increase

Single-molecule magnets (SMMs) hold promise for unmatched information storage density as well as applications in quantum computing and spintronics. To date, the most successful SMMs are organometallic lanthanide complexes. However, their surface immobilization, one of the requirements for device fabrication and commercial application, remains challenging due to sensitivity of magnetic properties to small changes in the electronic structure of the parent SMM. Thus, finding controlled approaches to SMM surface deposition is a timely challenge. In this contribution we apply the concept of isolobality to identify siloxides present at the surface of partially dehydroxylated silica as a suitable replacement for archetypal ligand architectures in organometallic SMMs. We demonstrate theoretically and experimentally that isolated siloxide anchorages not only enable successful immobilization, but also lead to two-orders-of-magnitude increase in magnetization relaxation times and provide magnetic site dilution.

scholarly journals Polarized light spectroscopy of azobenzene or disperse red 1 with Mn12 single-molecule magnets in PMMA film hybrid materials

2009 ◽  
Vol 7 (4) ◽  
pp. 690-696 ◽  
Author(s):  
Takashiro Akitsu ◽  
Chiaki Ishioka ◽  
Tsubasa Itoh
Keyword(s):  
Polymethyl Methacrylate ◽  
Hybrid Materials ◽  
Single Molecule ◽  
Ac Susceptibility ◽  
Polarized Light ◽  
Pmma Film ◽  
Single Molecule Magnets ◽  
Single Molecule Magnet ◽  
Photochromic Compounds ◽  
Disperse Red 1

AbstractA series of organic/inorganic hybrid materials containing the single-molecule magnet [Mn12(CH3COO)16(H2O)4O12]·2CH3COOH·4H2O with the photochromic compounds azobenzene or disperse red 1 cast into polymethyl methacrylate films was prepared. To understand the photomodulation of analogous mixtures’ AC susceptibility, we investigated the molecular alignment based on Weigert’s effect accompanying cycles of cis-trans photoisomerization by alternate irradiations with polarized UV and visible light. Polarized electronic spectra of the hybrid materials demonstrated gradually increasing anisotropy. These features suggest interactions between photochromic compounds and the Mn12 complex in polymethyl methacrylate.

Sign in / Sign up

Export Citation Format

Share Document