Ab initio study of the antiferromagnetic coupling in the wheel-shaped [Cu20Cl(OH)24(H2O)12(P8W48O184)]25- anion
Related Experiment Video
Updated: Jun 15, 2026
Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Coen de Graaf1, Xavier López, José Luis Ramos
1Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, C/Marcel.lí, Domingo, s/n, 43007, Tarragona, Spain. coen.degraaf@urv.cat
Abstract:
The most stable spin configuration in the Cu(20) unit embedded in the P(8)W(48)O(184) POM framework has been analyzed with ab initio computational methods. Because of the large size of the Cu(20) unit, a fragment approach has been adopted to compute the four possible magnetic interactions. Difference Dedicated Configuration Interaction results reveal that the magnetic coupling between unpaired copper electrons ranges from ferromagnetic (J = 14.8 cm(-1)) to antiferromagnetic (J = -72.6 cm(-1)). With the four calculated J-values we have performed a simulation of the magnetic susceptibility vs. temperature by using the Ising model and a Monte Carlo algorithm to sample the spin configurations. The most stable spin alignment, governed by the most intense antiferromagnetic interaction, features 12 up and 8 down spins. There is no full cancellation of spins that can comply with the magnetic interactions found for this molecule.
More Related Videos
09:06Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
08:55Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Related Concept Videos
02:42Valence Bond Theory
03:02Colors and Magnetism
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 eye.
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:42Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
01:22Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
02:46Crystal Field Theory - Tetrahedral and Square Planar 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,...