Keiichi Katoh

The crystal structures of double-decker single molecule magnets (SMM) LnPc(2) (Ln = Tb(III) and Dy(III); Pc = phthalocyanine) and non-SMM YPc(2) were determined by using X-ray diffraction analysis. The compounds are isomorphous to each other. The compounds have metal centers (M = Tb(3+), Dy(3+), and Y(3+)) sandwiched by two Pc ligands via eight isoindole-nitrogen atoms in a square-antiprism fashion. The twist angle between the two Pc ligands is 41.4 degrees. Scanning tunneling microscopy was use

A single magnet in a triple decker! TbIII–phthalocyaninate triple-decker 1, which has a center of symmetry, showed two magnetic relaxation processes in the low-temperature region in the presence of a direct current (dc) magnetic field. These results suggest that the single-molecule magnet/magnetic properties of 1 undergo a significant transition in a dc magnetic field. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed,

The SMM behaviour of dinuclear Ln(III)-Pc multiple-decker complexes (Ln = Tb(3+) and Dy(3+)) with energy barriers and slow-relaxation behaviour were explained by using X-ray crystallography and static and dynamic susceptibility measurements. In particular, interactions among the 4f electrons of several dinuclear Ln(III)-Pc type SMMs have never been discussed on the basis of the crystal structure. For dinuclear Tb(III)-Pc complexes, a dual magnetic relaxation process was observed. The relaxation

Magnetic dipole interactions are dominate in quasi one-dimensional (1D) molecular magnetic materials, in which TbNcPc units (Tb³⁺ =terbium(III) ion, Nc^2- =naphthalocyaninato, Pc^2- =phthalocyaninato) adopt a structure similar to TbPc₂ single-molecule magnets (SMMs). The magnetic properties of the [TbNcPc]^0/+ (neutral 1 and cationic 2) with 1D structures are significantly different from those of a magnetically diluted sample (3). In particular

Unlike electronics, which is based on the freedom of the charge of an electron whose memory is volatile, spintronics is based on the freedom of the charge, spin, and orbital of an electron whose memory is non-volatile. Although in most GMR, TMR, and CMR systems, bulk or classical magnets that are composed of transition metals are used, this Focus Review considers the growing use of single-molecule magnets (SMMs) that are composed of multinuclear metal complexes and nanosized magnets, which exhib

The single-molecule magnet (SMM) behaviour of dinuclear Ln(III)-Pc triple-decker complexes (Dy(III)-Y(III): 1 and Dy(III)-Dy(III): 2) with the same octacoordination environment and slow magnetic relaxation behaviour were explained using X-ray crystallography and static and dynamic susceptibility measurements. In particular, interactions among the 4f electrons of dinuclear Dy(III)-Pc triple-decker type SMMs have never been discussed on the basis of the same octacoordination environment. Our resul

Single-molecule magnet (SMM) properties of terbium(iii)-phthalocyaninato and porphyrinato mixed ligand triple-decker complexes, [(TTP)Tb(Pc)Tb(TTP)] (<b>1</b>) and [(Pc)Tb(Pc)Tb(TTP)] type (<b>2</b>), were studied and were compared with those of the Tb^III homoleptic triple-decker complex [(obPc)Tb(obPc)Tb(obPc)] (<b>3</b>) in order to elucidate the relationship between octa-coordination environments and SMM properties (Tb^III = terbium(iii), TTP^2- = tetraphenylpor

The crystal structures of double-decker single-molecule magnets (SMMs) LnPc(2) (Ln = Tb(III) and Dy(III); Pc = phthalocyanine) and non-SMM YPc(2) were determined by using single crystal X-ray diffraction analysis. The compounds are isomorphous to each other. The compounds have metal-centers (M(3+) = Tb, Dy, and Y) sandwiched by two Pc ligands via eight isoindole-nitrogen atoms in a square-antiprism fashion. The twist angle between the two Pc ligands is 41.4 degrees. Scanning tunneling microscopy

We have synthesized the novel organic polyradicals BIP-BNO and BIP-TENO, which crystallize to form spin systems with a double spin chain, where BIP-BNO and BIP-TENO denote 3,5'-bis( N - t e r t -butylaminoxyl)-3',5-dibromobiphenyl and 3,3',5,5'-tetrakis( N - t e r t -butylaminoxyl)biphenyl, respectively. The crystals of BIP-BNO form a two-leg ladder of S =1/2 with antiferromagnetic legs and rungs. The ground state of this material is singlet. The BIP-TENO molecule includes S =1/2 spin pairs (dim

Ever since the first example of a double-decker complex (SnPc2) was discovered in 1936, MPc2 complexes with π systems and chemical and physical stabilities have been used as components in molecular electronic devices. More recently, in 2003, TbPc2 complexes were shown to be single-molecule magnets (SMMs), and researchers have utilized their quantum tunneling of the magnetization (QTM) and magnetic relaxation behavior in spintronic devices. Herein, recent developments in Ln(III)-Pc-based multiple

When applying single-molecule magnets (SMMs) to spintronic devices, control of the quantum tunneling of the magnetization (QTM) as well as a spin-lattice interactions are important. Attempts have been made to use not only coordination geometry but also magnetic interactions between SMMs as an exchange bias. In this manuscript, dinuclear dysprosium(III) (Dy^III ) SMMs with the same octacoordination geometry undergo dual magnetic relaxation processes at low temperature. In the dinuclear

A one-dimensional (1D) arrangement of an unsubstituted partially oxidized Dy³⁺ double-decker complex, [DyPc₂ ]I_x (Pc=phthalocyaninato, I=iodide; 1.93<x<2.26) (1), was obtained by using electro-oxidation and chemical oxidation. In 1, the Pc ligands were partially oxidized, and I₃ ^- ion was present as a counter ion. From the results of spectrophotometric analysis on 1, the π radicals were delocalized in a 1D column and behaved as a conductor e

Single-molecule magnet (SMM) properties of crystals of a terbium(III)-phthalocyaninato double-decker complex with different molecular packings (<b>1</b>: TbPc₂, <b>2</b>: TbPc₂·CH₂Cl₂) were studied to elucidate the relationship between the molecular packing and SMM properties. From single crystal X-ray analyses, the high symmetry of the coordination environment of <b>2</b> suggested that the SMM properties were improved. Furthermore, the shorter intermolecular Tb-Tb distance and relative colline