Related Experiment Video
Updated: May 23, 2025
11:19
Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels
Published on: July 4, 2016
10.6K
Multiple spin reorientation transitions in Ga3+-substituted DyCrO3
Xiong-Han Liu1, Meng-Qi Ye1, Hai-Bo Xiao1
1Key Laboratory for Intelligent Sensing System and Security of Ministry of Education, School of Physics, Hubei University, Wuhan 430062, People's Republic of China. wangrl@hubu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|March 11, 2025
Summary
Gallium substitution in DyCrO3 induces multiple spin reorientation transitions, unlike pure DyCrO3. These findings highlight DyCr1-xGaxO3 as a promising material for magnetic switching devices.
Area of Science:
- Solid State Chemistry
- Magnetism and Magnetic Materials
- Rare-Earth Compounds
Background:
- Rare-earth orthochromites exhibit complex magnetic phenomena.
- Spin reorientation transitions are crucial for magnetic applications.
- Understanding substitution effects is key to tuning material properties.
Purpose of the Study:
- To synthesize and characterize single-phase DyCr1-xGaxO3 (0 ≤ x ≤ 0.5) samples.
- To investigate the impact of Ga3+ substitution on magnetic properties, specifically spin reorientation transitions.
- To explore the potential of these materials for magnetic switching devices.
Main Methods:
- Sol-gel synthesis method for sample preparation.
- Magnetic measurements to determine magnetic transitions and susceptibility.
- Analysis of temperature-dependent inverse susceptibility to identify phases.
Main Results:
- Single-phase DyCr1-xGaxO3 samples were successfully synthesized.
- Ga3+ substituted samples exhibited multiple spin reorientation transitions (Γ2 → Γ4 → Γ2 → Γ1), a novel observation in rare-earth orthochromites.
- A Griffiths phase was identified in Ga3+ substituted samples.
- The observed magnetic behavior is attributed to weakened exchange interactions due to Ga3+ substitution.
Conclusions:
- Ga3+ substitution in DyCrO3 leads to unprecedented multiple spin reorientation transitions.
- The presence of the Griffiths phase and multiple transitions suggests rich magnetic structures.
- DyCr1-xGaxO3 materials show promise for applications in magnetic switching devices.
Related Concept Videos
01:03Atomic Nuclei: Nuclear Spin State Overview
841
NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of...
841
01:23Atomic Nuclei: Nuclear Relaxation Processes
598
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis.
598
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
938
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
938
01:17Spin–Spin Coupling: One-Bond Coupling
920
Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
920
01:08NMR Spectroscopy: Spin–Spin Coupling
1.2K
The spin state of an NMR-active nucleus can have a slight effect on its immediate electronic environment. This effect propagates through the intervening bonds and affects the electronic environments of NMR-active nuclei up to three bonds away; occasionally, even farther. This phenomenon is called spin–spin coupling or J-coupling. Coupling interactions are mutual and result in small changes in the absorption frequencies of both nuclei involved. While nuclei of the same element are involved...
1.2K
01:05Atomic Nuclei: Magnetic Resonance
602
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
602