In this article, we investigate a single molecule magnet bis(phthalocyaninato)terbium(iii) (TbPc) molecule film by using low temperature STM. In order to investigate the effect of molecule-substrate interaction on the electronic and spin properties of the adsorbed molecule, we tune the molecule-substrate coupling by switching the substrate between Au(111) and Ag(111), the latter of which provides stronger interaction with the molecule than the former. Despite the enhanced chemical reactivity of the Ag(111) surface compared with Au(111), a well-organized pseudo-square film is formed. In addition, a checker-board type contrast variation is identified, which is well explained by the existence of two types of molecules whose rotational angle between the top and bottom Pc is θ = 45° (bright molecule) and θ = 30° (dark molecule). The expected stronger molecule-substrate interaction, however, appears as an intriguing dI/dV mapping image which reveals the spatial distribution of the density of states (DOS). We identify the contrast reversal in the dI/dV mapping for the molecules of θ = 45° and θ = 30° at the sample voltages of V = 0.7 eV and 1.1 eV. Combined with the density functional theory (DFT) calculation, we attribute this change to the shift of an electronic state due to the rotation of the mutual angle between the top and bottom Pc. For the spin behavior, we previously observed a Kondo resonance for the TbPc molecule adsorbed on the Au(111) surface. On the Ag(111) surface, the Kondo resonance is hardly observed, which is due to the annihilation of the π radical spin by the charge transfer from the substrate to the molecule. Instead we observe a Kondo peak for the molecule on the second layer, for which the spin recovers due to the reduction of the coupling with the substrate. In addition, when a magnetic field of 2 T normal to the surface is applied, the second layer molecule shows a sharp dip at the Fermi level. We attribute this to the inelastic tunneling feature caused by the spin flipping. This feature is not observed for the TbPc/Au(111) system, suggesting that the decoupling between the TbPc molecule and Ag(111) by the presence of the first layer produces an inelastic feature in the tunneling spectra.

We demonstrate a direct visualization of the magnetic hysteresis of a single-molecule magnet bis(phthalocyaninato)terbium(III) (TbPc2) adsorbed on the Co islands, which covers a submonolayer region of an Au(111) surface by utilizing the spin-polarized scanning tunneling microscope (SP-STM) and monitoring the magnetotunneling resistance. We found that the TbPc2 molecule is spin polarized and attached to the ferromagnetic Co islands. The result of the SP-STM measurements showed that the spin of TbPc2 is antiferromagnetically coupled to the magnetization of the Co island. In addition, we found an opening in the hysteresis curve even with the frozen magnetization of the Co island, unlike that with near-zero remanence typically reported for the bulk crystal and the nonmagnetic substrate.

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In this study, terbium(III) bis-phthalocyaninato single-molecule magnets (TbPc2 SMMs) were encapsulated in the internal nano space of single-walled carbon nanotubes (SWCNTs) for the first time. The magnetic and electronic properties...

Here, the first-principles predictions on the structural stability, magnetic behavior and electronic structure of B-site ordered double perovskite Nd$_2$CrFeO$_6$ have been reported. Initially, the ground state of the parent single...

We investigated the spin properties of the terbium phthalocyanine (TbPc) species adsorbed on the superconductor NbSe 2 surface using scanning tunneling microscopy and spectroscopy. TbPc 2 is a molecule in a class of single-molecule magnets (SMMs), and the use of superconductor electrodes attracts attention for the application to the devices using the spin degree of freedom. TbPc is a building block of TbPc 2 and can reveal the spin component’s behavior. In the experiment, TbPc species were placed on the surface of the superconductor NbSe 2 . We measured Yu–Shiba–Rusinov (YSR) states caused by the interaction between the superconducting state and magnetic impurity and inelastic tunneling spectroscopy (IETS) for the spin excitation, below 1 K. We also measured the Kondo state formed by the magnetic singlet formation. We detected the radical spin at the ligand position of the TbPc by the presence of the Kondo peak and demonstrated that the radical spin forms the YSR feature. In addition, the exchange interaction energy ( E ex ) between the spins of the radical ligand (Pc) and the center 4f metal atom (Tb 3+ ) is determined by using the IETS technique. E ex is a critical parameter that determines the blocking temperature, below which the sample behaves as an SMM. IETS results show that the statistical distribution of E ex has peaked at 1.3, 1.6, and 1.9 meV. The energy range is comparable to the recent theoretical calculation result. In addition, we show that the energy variation is correlated with the bonding configuration of TbPc.

We explored a comprehensive comparison of the structure-property relationships between sillenite and perovskite phases of Bi0.9Dy0.1FeO3 (BDFO) nanostructures synthesized by hydrothermal (HT) and sol-gel (SG) techniques. The role of sillenite/perovskite...

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