Spin Exchanges between Transition Metal Ions Governed by the Ligand p-Orbitals in Their Magnetic Orbitals

In this review on spin exchanges, written to provide guidelines useful for finding the spin lattice relevant for any given magnetic solid, we discuss how the values of spin exchanges in transition metal magnetic compounds are quantitatively determined from electronic structure calculations, which el...

Full description

Bibliographic Details
Main Authors: Myung-Hwan Whangbo, Hyun-Joo Koo, Reinhard K. Kremer
Format: Article
Language:English
Published: MDPI AG 2021-01-01
Series:Molecules
Subjects:
Online Access:https://www.mdpi.com/1420-3049/26/3/531
_version_ 1797409210488586240
author Myung-Hwan Whangbo
Hyun-Joo Koo
Reinhard K. Kremer
author_facet Myung-Hwan Whangbo
Hyun-Joo Koo
Reinhard K. Kremer
author_sort Myung-Hwan Whangbo
collection DOAJ
description In this review on spin exchanges, written to provide guidelines useful for finding the spin lattice relevant for any given magnetic solid, we discuss how the values of spin exchanges in transition metal magnetic compounds are quantitatively determined from electronic structure calculations, which electronic factors control whether a spin exchange is antiferromagnetic or ferromagnetic, and how these factors are related to the geometrical parameters of the spin exchange path. In an extended solid containing transition metal magnetic ions, each metal ion M is surrounded with main-group ligands L to form an ML<sub>n</sub> polyhedron (typically, n = 3–6), and the unpaired spins of M are represented by the singly-occupied d-states (i.e., the magnetic orbitals) of ML<sub>n</sub>. Each magnetic orbital has the metal d-orbital combined out-of-phase with the ligand p-orbitals; therefore, the spin exchanges between adjacent metal ions M lead not only to the M–L–M-type exchanges, but also to the M–L…L–M-type exchanges in which the two metal ions do not share a common ligand. The latter can be further modified by d<sup>0</sup> cations A such as V<sup>5+</sup> and W<sup>6+</sup> to bridge the L…L contact generating M–L…A…L–M-type exchanges. We describe several qualitative rules for predicting whether the M–L…L–M and M–L…A…L–M-type exchanges are antiferromagnetic or ferromagnetic by analyzing how the ligand p-orbitals in their magnetic orbitals (the ligand p-orbital tails, for short) are arranged in the exchange paths. Finally, we illustrate how these rules work by analyzing the crystal structures and magnetic properties of four cuprates of current interest: α-CuV<sub>2</sub>O<sub>6</sub>, LiCuVO<sub>4</sub>, (CuCl)LaNb<sub>2</sub>O<sub>7</sub>, and Cu<sub>3</sub>(CO<sub>3</sub>)<sub>2</sub>(OH)<sub>2</sub>.
first_indexed 2024-03-09T04:11:05Z
format Article
id doaj.art-ddd9f39f981a4cfd805862b6d943225d
institution Directory Open Access Journal
issn 1420-3049
language English
last_indexed 2024-03-09T04:11:05Z
publishDate 2021-01-01
publisher MDPI AG
record_format Article
series Molecules
spelling doaj.art-ddd9f39f981a4cfd805862b6d943225d2023-12-03T14:00:55ZengMDPI AGMolecules1420-30492021-01-0126353110.3390/molecules26030531Spin Exchanges between Transition Metal Ions Governed by the Ligand p-Orbitals in Their Magnetic OrbitalsMyung-Hwan Whangbo0Hyun-Joo Koo1Reinhard K. Kremer2Department of Chemistry and Research Institute for Basic Sciences, Kyung Hee University, Seoul 02447, KoreaDepartment of Chemistry and Research Institute for Basic Sciences, Kyung Hee University, Seoul 02447, KoreaMax Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, GermanyIn this review on spin exchanges, written to provide guidelines useful for finding the spin lattice relevant for any given magnetic solid, we discuss how the values of spin exchanges in transition metal magnetic compounds are quantitatively determined from electronic structure calculations, which electronic factors control whether a spin exchange is antiferromagnetic or ferromagnetic, and how these factors are related to the geometrical parameters of the spin exchange path. In an extended solid containing transition metal magnetic ions, each metal ion M is surrounded with main-group ligands L to form an ML<sub>n</sub> polyhedron (typically, n = 3–6), and the unpaired spins of M are represented by the singly-occupied d-states (i.e., the magnetic orbitals) of ML<sub>n</sub>. Each magnetic orbital has the metal d-orbital combined out-of-phase with the ligand p-orbitals; therefore, the spin exchanges between adjacent metal ions M lead not only to the M–L–M-type exchanges, but also to the M–L…L–M-type exchanges in which the two metal ions do not share a common ligand. The latter can be further modified by d<sup>0</sup> cations A such as V<sup>5+</sup> and W<sup>6+</sup> to bridge the L…L contact generating M–L…A…L–M-type exchanges. We describe several qualitative rules for predicting whether the M–L…L–M and M–L…A…L–M-type exchanges are antiferromagnetic or ferromagnetic by analyzing how the ligand p-orbitals in their magnetic orbitals (the ligand p-orbital tails, for short) are arranged in the exchange paths. Finally, we illustrate how these rules work by analyzing the crystal structures and magnetic properties of four cuprates of current interest: α-CuV<sub>2</sub>O<sub>6</sub>, LiCuVO<sub>4</sub>, (CuCl)LaNb<sub>2</sub>O<sub>7</sub>, and Cu<sub>3</sub>(CO<sub>3</sub>)<sub>2</sub>(OH)<sub>2</sub>.https://www.mdpi.com/1420-3049/26/3/531<b>Keywords</b>: spin exchangemagnetic orbitalsligand p-orbital tailsM–L–M exchangeM–L…L–M exchangeα-CuV<sub>2</sub>O<sub>6</sub>
spellingShingle Myung-Hwan Whangbo
Hyun-Joo Koo
Reinhard K. Kremer
Spin Exchanges between Transition Metal Ions Governed by the Ligand p-Orbitals in Their Magnetic Orbitals
Molecules
<b>Keywords</b>: spin exchange
magnetic orbitals
ligand p-orbital tails
M–L–M exchange
M–L…L–M exchange
α-CuV<sub>2</sub>O<sub>6</sub>
title Spin Exchanges between Transition Metal Ions Governed by the Ligand p-Orbitals in Their Magnetic Orbitals
title_full Spin Exchanges between Transition Metal Ions Governed by the Ligand p-Orbitals in Their Magnetic Orbitals
title_fullStr Spin Exchanges between Transition Metal Ions Governed by the Ligand p-Orbitals in Their Magnetic Orbitals
title_full_unstemmed Spin Exchanges between Transition Metal Ions Governed by the Ligand p-Orbitals in Their Magnetic Orbitals
title_short Spin Exchanges between Transition Metal Ions Governed by the Ligand p-Orbitals in Their Magnetic Orbitals
title_sort spin exchanges between transition metal ions governed by the ligand p orbitals in their magnetic orbitals
topic <b>Keywords</b>: spin exchange
magnetic orbitals
ligand p-orbital tails
M–L–M exchange
M–L…L–M exchange
α-CuV<sub>2</sub>O<sub>6</sub>
url https://www.mdpi.com/1420-3049/26/3/531
work_keys_str_mv AT myunghwanwhangbo spinexchangesbetweentransitionmetalionsgovernedbytheligandporbitalsintheirmagneticorbitals
AT hyunjookoo spinexchangesbetweentransitionmetalionsgovernedbytheligandporbitalsintheirmagneticorbitals
AT reinhardkkremer spinexchangesbetweentransitionmetalionsgovernedbytheligandporbitalsintheirmagneticorbitals