Related Experiment Video
Updated: Mar 18, 2026
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
8.7K
Tetramer spin singlet instability in the fluorine-substituted pyrochlore superconducting system Cd2Re2O7-x F x
Yuya Haraguchi1, Chishiro Michioka1, Hiroaki Ueda1
1Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
Summary
Fluorine substitution in Cd2Re2O7-x F x pyrochlore rhenates influences structural and magnetic properties. This study reveals unconventional superconductivity in these spin-frustrated materials, with critical fields exceeding the Pauli limit.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Pyrochlore rhenates (Cd2Re2O7) exhibit complex magnetic and transport properties.
- Spin frustration in pyrochlore lattices can lead to exotic electronic states.
- Fluorine substitution is explored as a method to tune material properties.
Purpose of the Study:
- To synthesize and characterize fluorine-substituted pyrochlore rhenates (Cd2Re2O7-x F x).
- To investigate the impact of fluorine substitution on structural, magnetic, and transport properties.
- To explore the superconducting behavior of these materials.
Main Methods:
- Polycrystalline sample synthesis.
- Magnetic property measurements.
- Transport property measurements.
- Structural property analysis.
Main Results:
- The structural transition temperature (T s1) decreases with increasing fluorine content (x).
- Magnetic and transport properties show strong dependence on fluorine content in the low-temperature phase.
- Unconventional superconducting properties were observed, with T c decreasing as x increases.
- The upper critical field exceeds the Pauli paramagnetic limit and increases with x, despite decreasing T c.
Conclusions:
- Spin frustration and tetramer spin singlet formation drive the structural phase transition.
- Cd2Re2O7-x F x exhibits exotic superconductivity in itinerant electron systems on a spin-frustrated lattice.
- Fluorine substitution tunes superconducting properties and suggests a route to manipulating exotic electronic states.
Related Concept Videos
02:42Valence Bond Theory
11.5K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
11.5K
03:02Colors and Magnetism
14.5K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
14.5K
01:31Ferromagnetism
3.4K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
3.4K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
49.5K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
49.5K
03:24Hybridization of Atomic Orbitals I
69.1K
The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically accomplished by the linear combination of atomic orbitals. The new orbitals that...
69.1K
03:35Hybridization of Atomic Orbitals II
50.1K
sp3d and sp3d 2 Hybridization
50.1K