Copper-Based Two-Dimensional Metal-Organic Frameworks for Fenton-like Photocatalytic Degradation of Methylene Blue under UV and Sunlight Irradiation.

To efficiently degrade organic pollutants, photocatalysts must be effective under both ultraviolet (UV) radiation and sunlight. We synthesized a series of new metal-organic frameworks by using mild hydrothermal conditions. These frameworks incorporate three distinct bipyridyl ligands: pyrazine (pyr), 4,4'-bipyridine (bpy), and 1,2-bis(4-pyridyl)ethane (bpe). The resulting compounds are denoted as [Cu(pyz)(H2O)2MF6], [Cu(bpy)2(H2O)2]·MF6, and [Cu(bpe)2(H2O)2]·MF6·H2O [M = Zr (1, 3, and 5) and Hf (2, 4, and 6)]. All six compounds exhibited a two-dimensional crystal structure comprising infinitely nonintersecting linear chains. Compound 3 achieved 100% degradation of methylene blue (MB) after 8 min under UV irradiation and 100 min under natural sunlight in the presence of H2O2 as the electron acceptor. For compound 5, 100% MB degradation was achieved after 120 min under sunlight and 10 min under UV light. Moreover, reactive radical tests revealed that the dominant species involved in photocatalytic degradation are hydroxyl (•OH), superoxide radicals (•O2-), and photogenerated holes (h+). The photodegradation process followed pseudo-first-order kinetics, with photodegradation rate constants of 0.362 min-1 (0.039 min-1) for 3 and 0.316 min-1 (0.033 min-1) for 5 under UV (sunlight) irradiation. The developed photocatalysts with excellent activity and good recyclability are promising green catalysts for degrading organic pollutants during environmental decontamination.

Molecular Flexibility in Solvated Crystals of the Dimer, Au2(µ-1,2-bis(diphenylphosphino)ethane)2I2, with Three-Coordinate Gold(I).

We report the ability to trap the dimer Au2(µ-dppe)2I2 (dppe is 1,2-bis(diphenylphosphino)ethane) with different separations between the three-coordinate gold ions in crystalline solvates. All of these solvates ((Au2(µ-dppe)2I2·4(CH2Cl2) (1), Au2(µ-dppe)2I2·2(CH2Cl2) (2), the polymorphs α-Au2(µ-dppe)2I2·2(HC(O)NMe2) (3) and ß-Au2(µ-dppe)2I2·2(HC(O)NMe2) (4), and Au2(µ-dppe)2I2·4(CHCl3) (5)) along with polymeric {Au(µ-dppe)I}n·n(CHCl3) (6)) originated from the same reaction, only the solvent system used for crystallization differed. In the different solvates of Au2(µ-dppe)2I2, the Au···Au separation varied from 3.192(1) to 3.7866(3) Å. Computational studies undertaken to understand the flexible nature of these dimers indicated that the structural differences were primarily a result of crystal packing effects with aurophillic interactions having a minimal effect.

Thermodynamic, Spectroscopic, and Structural Study on a Sodium Uranyl Tri-2-Methoxybenzoate Dodecahydrate Coordination Compound with Considerably Low Solubility in Acidic Conditions.

A spontaneous crystallization of an uranium(VI)-organic coordination compound with sodium and 2-methoxybenzoate (2-mba) was observed in acidic solutions, and the solubility product, molecular vibrations, crystal structure, thermal stability, and emission properties of the atypically low-soluble U(VI) complex (Na[UO2(2-mba)3]·12H2O(s)) were fully investigated for the first time. A long-term solubility experiment and speciation modeling gave a solubility product of log Ks,0 = -12.18 ± 0.02 (T = 25 °C and I = 0.1 M NaClO4), and vibrational analyses confirmed the overall molecular structure of complex and the frequencies of characteristic stretching motions of uranyl moiety as well. The crystal quality of Na[UO2(2-mba)3]·12H2O(s) was improved by a digestion method, and X-ray diffraction analysis of the single crystalline specimen verified that the newly studied uranyl-organic compound contains one-dimensional channels with a diameter of 20 Å along the [001] direction; the sodium and water molecules are arranged in the channel structures. In the coordination environment around uranyl, three aromatic carboxylates are symmetrically bound in the equatorial plane of uranyl coplanarily, and the unit [UO2(2-mba)3]- complexes are further extended along the plane to form the layered-morphologies. The three-dimensional packing of [UO2(2-mba)3]- anions is driven by the parallel-displaced π-stacking of aromatic rings with a centroid-centroid distance of 3.7 Å. Additional thermogravimetric analysis confirmed that the Na[UO2(2-mba)3]·12H2O(s) is stable up to 250 °C, and dehydration and release of the organic ligand were subsequently observed beyond that temperature. Photoluminescence spectrum of the Na[UO2(2-mba)3]·12H2O(s) clearly displayed the characteristic U(VI) emission, and a band spacing between the ground electronic states of U(VI) uranyl was evaluated to be 831 ± 14 cm-1. Such detailed characterization of the unique Na[UO2(2-mba)3]·12H2O(s) is advancing upon a systematic understanding of the structural effects of the aromatic model ligands on U(VI) complexation, with relevance to the environmental chemistry of U(VI) and crystal engineering for development of diverse uranyl-organic frameworks.

KIn0.33IIITe0.67VITe2IVO7: Zirconolite-like Mixed-Valent Metal Oxide with a 3D Framework.

We provide the material synthesis method, crystal structure information, and characterization of a novel mixed-valent metal oxide KIn0.33IIITe0.67VITe2IVO7, closely related to zirconolite (CaZrTi2O7), a radioactive waste immobilized material, having a 3D framework. The reported metal oxide containing an alkali-metal cation (K+), main-group cation (In3+), tellurate, and tellurite has been synthesized as both single crystals and a pure polycrystalline phase through a hydrothermal synthesis method. Single-crystal X-ray diffraction indicates that KIn0.33Te2.67O7 crystallizing in the orthorhombic space group Cmcm (No. 63) reveals a 3D framework structure with a 1D channel consisting of Te/InO6 octahedra and TeO4 polyhedra. An interesting transition reaction from KIn0.33Te2.67O7 to KIn(TeO3)2 under hydrothermal conditions at 230 °C is discussed.

Vapoluminescent Behavior and the Single-Crystal-to-Single-Crystal Transformations of Chloroform Solvates of [Au2 (µ-1,2-bis(diphenylarsino)ethane)2 ](AsF6 )2.

The mono- and di-chloroform solvates of [Au2 (µ-1,2-bis(diphenylarsino)ethane)2 ](AsF6 )2 undergo single-crystal-to-single-crystal transformations that result in gain (over 12 hours) or slow loss (over five years) of only one chloroform molecule. The change in solvation results in changes in the structure and luminescence of the digold cation. The cation consists of a pair of slightly bent As-Au-As units that are connected through the two bridging dpae ligands and by aurophilic interactions with Au⋅⋅⋅Au contacts of 3.05152(15) Šin the disolvate or 2.9570(5) Šin the monosolvate.

Optimal Respiratory Rate for Low-Tidal Volume and Two-Lung Ventilation in Thoracoscopic Bleb Resection.

OBJECTIVES: One-lung ventilation is considered to be mandatory in video-assisted thoracoscopic surgery. However, the authors showed in a previous report that two-lung ventilation with low tidal volume is feasible in thoracoscopic bleb resection (TBR). In this study, they evaluated optimal respiratory rate during TBR under two-lung ventilation with low-tidal volume anesthesia. DESIGN: A prospective, randomized, single-blinded intervention study. SETTING: An operating room in a teaching hospital. PARTICIPANTS: Forty-eight patients who underwent scheduled TBR under general anesthesia. INTERVENTIONS: TBR was performed under low-tidal-volume (5 mL/kg), two-lung ventilation. Respiratory rate (RR) varied according to the protocol: 15 (group I), 18 (group II), and 22 cycles/min (group III). Using block randomization method, 16 patients were assigned to each of 3 groups. MEASUREMENTS AND MAIN RESULTS: Minute ventilation of group I was lowered significantly compared with the other groups (p<0.001). The results of arterial blood gas analysis were in the physiologic range in all patients. Surgery and anesthetic times and number of endostaples used were not significantly different among the 3 groups. CONCLUSIONS: The RR of 15 cycles/min with low-tidal volume (5 mL/kg) and two-lung ventilation did not produce abnormal physiologic changes including arterial pH, partial arterial oxygen pressure, and partial pressure of carbon dioxide and guaranteed an optimal surgical field. Therefore, these setting are considered acceptable for two-lung ventilation during TBR.

Self-assembled supramolecular clusters based on phosphines and coinage metals: tetrahedra, helicates, and mesocates.

An array of coordination-driven supramolecular metal-ligand clusters has been synthesized using polytopic phosphine ligands and coinage metals (Cu(+), Ag(+), Au(+)). Rigid 3-fold or 2-fold symmetric phosphine ligands have been prepared: 1,3,5-tris((4-(diphenylphosphino)ethynyl)phenyl)benzene) (tppepb, L(1)), 1,4-bis((diphenylphosphino)ethynyl)benzene (1,4-dppeb, L(2)), 1,3-bis((diphenylphosphino)ethynyl)benzene (1,3-dppeb, L(3)), 2,6-bis((diphenylphosphino)ethynyl)pyridine (2,6-dppep, L(4)), and 1,5-bis((diphenylphosphino)ethynyl)naphthalene (1,5-dppen, L(5)). Self-assembly of these ligands with coinage metals produces four different types of metal-ligand clusters, or in some cases coordination polymers, depending on number and relative geometry of the phosphine donor atoms. Supramolecular tetrahedral clusters of the formula M4(L(1))4I4 (M = Cu(+), Ag(+), Au(+)) were obtained with the tppepb ligand, encapsulating solvent molecules (either CH2Cl2 or DMF) as guests within the central cavity of the clusters. The ligands 1,3-dppeb (L(3)) and 2,6-dppep (L(4)) give achiral, triple-stranded, dinuclear mesocates with the formula M2(L)3I2 (M = Cu(+) or Au(+)). In contrast, the ligand 1,4-dppeb (L(2)) generates a triple-stranded, dinuclear helicate with Cu(+), but a coordination polymer with Au(+) (both with the empirical formula M2(L(2))3I2). Finally, coordination polymers were obtained from 1,5-dppen (L(5)) with Cu(+). The clusters have been fully characterized by single crystal X-ray crystallography, high-resolution mass spectrometry, (1)H NMR, and (31)P NMR.

Crystallographic and computational studies of luminescent, binuclear gold(I) complexes, Au(I)2(Ph2P(CH2)nPPh2)2I2 (n = 3-6).

Four crystalline dimers of the type, Au(I)(2)(µ-PnP)(2)I(2), where PnP is PPh(2)(CH(2))(n)PPh(2) with n = 3, 4, 5, and 6 have been prepared and characterized by single-crystal X-ray diffraction and by (31)P NMR and infrared spectroscopy. Au(I)(2)(µ-P3P)(2)I(2) and Au(I)(2)(µ-P6P)(2)I(2) are centrosymmetric dimers with the planar Au(I)P(2)I units oriented in antiparallel fashion. Remarkably, noncentrosymmetric Au(I)(2)(µ-P5P)(2)I(2) has its planar Au(I)P(2)I units oriented in parallel manner. Au(I)(2)(µ-P4P)(2)(µ-I)(2) is unique, since it contains four-coordinate gold centers that are bridged by both iodide and diphosphine ligands. All four compounds are luminescent as solids at room temperature. B3LYP, B2PLYP, and spectroscopically oriented configuration interaction (SORCI) calculations have been conducted to give insight into the electronic and geometric structures of the ground and first excited triplet states of the three trigonal-planar complexes. The emission energies for the trigonal planar complexes are more strongly correlated with changes in the Au-I bond length rather than changes in the P-Au-P angle.

Thermal stability and critical switching field of nanostructured synthetic ferrimagnets.

In this study, the thermal stability and critical switching field of nanostructured elliptical synthetic ferrimagnets are calculated by using an analytical/numerical combined method, and the relationship between the two parameters is investigated. In conventional single magnetic layers, the critical switching field is a good measure of the thermal stability since the anisotropy, which determines the thermal stability, scales with the critical switching field. However, no such correlation is expected in nanostructured synthetic ferrimagnets, where the anisotropy is poorly defined owing to the strong interlayer magnetostatic interactions between two magnetic layers. This behavior is explained by the difference in the variation of the thermal stability with the external magnetic field as a function of the thickness asymmetry between two magnetic layers. The variation is found to be smaller at a smaller thickness asymmetry, where the interlayer magnetostatic coupling is stronger. This result indicates that the correlation between the two parameters is poorest in the completely symmetric synthetic ferrimagnet, but it increases with increasing thickness asymmetry of the synthetic ferrimagnets.

Crystallization and interconversions of vapor-sensitive, luminescent polymorphs of [(C6H11NC)2Au(I)](AsF6) and [(C6H11NC)2Au(I)](PF6).

The remarkable, vapor-induced transformation of the yellow polymorphs of [(C(6)H(11)NC)(2)Au(I)](AsF(6)) and [(C(6)H(11)NC)(2)Au(I)](PF(6)) into the colorless forms are reported along with related studies of the crystallization of these polymorphs. Although the interconversion of these polymorphs is produced by vapor exposure, molecules of the vapor are not incorporated into the crystals. Thus, our observations may have broad implications regarding the formation and persistence of other crystal polymorphs where issues of stability and reproducibility of formation exist. Crystallographic studies show that the colorless polymorphs, which display blue luminescence, are isostructural and consist of linear chains of gold(I) cations that self-associate through aurophilic interactions. Significantly, the yellow polymorph of [(C(6)H(11)NC)(2)Au(I)](AsF(6)) is not isostructural with the yellow polymorph of [(C(6)H(11)NC)(2)Au(I)](PF(6)). Both yellow polymorphs exhibit green emission and have the gold cations arranged into somewhat bent chains with significantly closer Au···Au separations than are seen in the colorless counterparts. Luminescence differences in these polymorphs clearly enhance the ability to detect and monitor their phase stability.

Polymorphs and aurophilic interactions in colorless crystals of Au2(µ-1,2 bis-(diphenylarsino)ethane)X2, (X = Cl, Br, I).

Solutions containing the components Au(+), dpae (dpae is 1,2 bis-(diphenylarsino)ethane), and X(-) (X is Cl, Br, or I) can produce two different types of crystals with the composition Au(2)(µ-dpae)X(2): colorless blocks and colorless needles. Crystallographic studies of these crystals show that they are polymorphs with different structural motifs. In the α-polymorphs, which are isostructural, individual molecules of Au(2)(µ-dpae)X(2) form discrete dimers through two identical Au···Au contacts. In the ß-polymorphs, which each have unique crystallographic parameters, the Au(2)(µ-dpae)X(2) molecules assemble into polymeric chains through aurophilic interactions. The Au···Au contacts in the α-polymorph (3.1163(2), 3.1064(3), and 3.0842(2) Å for Cl, Br, I, respectively) are somewhat shorter than those in the ß-polymorph (3.1668(3), 3.1042(8), and 3.1046(2) for Cl, Br, I respectively). The systematic study we now report shows an increase in the strength of this aurophilic interaction for the α-form in the series X = Cl < Br < I, which is in good agreement with theoretical studies by Pyykkö and his co-workers.

Structural and spectroscopic studies of spontaneously formed crystalline Eu(iii)-aliphatic dicarboxylates at room temperature.

Complexation of actinides and lanthanides with carboxylic organic ligands is a critical issue affecting radionuclide migration from deep geological disposal systems of spent nuclear fuel. A series of Eu(iii)-aliphatic dicarboxylate compounds, as chemical analogs of radioactive Am(iii) species, Eu2(Ox)3(H2O)6, Eu2(Mal)3(H2O)6, and Eu2(Suc)3(H2O)2, were synthesized and characterized using X-ray crystallography and time-resolved laser fluorescence spectroscopy to examine the ligand-dependent binding modes and the corresponding changes in spectroscopic properties. Powder X-ray crystallography results confirmed that all of the compounds presented a crystalline polymer structure with a trigonal prism square-face tricapped polyhedron geometry centered on Eu(iii) in a nine-coordinate environment involving nine oxygen atoms. This study captures the transition of the coordination modes of aliphatic dicarboxylate ligands from side-on to end-on binding as the carbon chain length increases. This transition is illustrated in malonate bindings involving a combination of side-on and end-on modes. Strongly enhanced luminescence, especially for the hypersensitive peak, indicates a low site symmetry in the formation of solid compounds. The number of remaining bound water molecules was estimated from the resultant increased luminescence lifetimes, which were in good agreement with crystal structures. The excitation-emission matrix spectra of these crystalline polymers suggest that Ox ligands promote the sensitized luminescence of Eu(iii), especially in the UV region. In the case of Mal and Suc ligands, charge transfer occurs in the opposite direction from Eu(iii) to the ligands under UV excitation, resulting in weaker luminescence.

Selective removal of radioactive iodine from water using reusable Fe@Pt adsorbents.

Environmental damage from serious nuclear accidents should be urgently restored, which needs the removal of radioactive species. Radioactive iodine isotopes are particularly problematic for human health because they are released in large amounts and retain radioactivity for a substantial time. Herein, we prepare platinum-coated iron nanoparticles (Fe@Pt) as a highly selective and reusable adsorbent for iodine species, i.e., iodide (I-), iodine (I2), and methyl iodide (CH3I). Fe@Pt selectively separates iodine species from seawater and groundwater with a removal efficiency ≥ 99.8%. The maximum adsorption capacity for the iodine atom of all three iodine species was determined to be 25 mg/g. The magnetic properties of Fe@Pt allow for the facile recovery and reuse of Fe@Pt, which remains stable with high efficiency (97.5%) over 100 uses without structural and functional degradation in liquid media. Practical application to the removal of radioactive 129I and feasibility for scale-up using a 20 L system demonstrate that Fe@Pt can function as a reusable adsorbent for the selective removal of iodine species. This systematic procedure is a standard protocol for designing highly active adsorbents for the clean separation and removal of various chemical species dissolved in wastewater.

Molecular accordion: vapoluminescence and molecular flexibility in the orange and green luminescent crystals of the dimer, Au2(µ-bis-(diphenylphosphino)ethane)2Br2.

Solutions containing the components Au(+), dppe (dppe is bis(diphenylphosphino)ethane), and Br(-) in a 1:1:1 ratio can produce three different types of crystals: type A, orange luminescent solvates of the dimer Au(2)(dppe)(2)Br(2) (Au(2)(µ-dppe)(2)Br(2)·2(OSMe(2)), Au(2)(µ-dppe)(2)Br(2)·2(OCMe(2)), Au(2)(µ-dppe)(2)Br(2)·2(CH(2)Cl(2)), Au(2)(µ-dppe)(2)Br(2)·2(HC(O)NMe(2))); type B, green luminescent solvates of the same dimer (Au(2)(µ-dppe)(2)Br(2)·(NCMe) and Au(2)(µ-dppe)(2)Br(2)·0.5(C(4)H(10)O)); and type C, orange luminescent solvates of a polymer ({Au(µ-dppe)Br}(n)·0.5(C(4)H(10)O) and {Au(µ-dppe)Br}(n)·(CH(2)Cl(2))). Some crystals of types A are solvoluminescent. Exposure of type A crystals of Au(2)(µ-dppe)(2)Br(2)·2(OCMe(2)) or Au(2)(µ-dppe)(2)Br(2)·2(CH(2)Cl(2)) to air or vacuum results in the loss of the orange luminescence and the formation of new green luminescent crystals. Subsequent exposure of these crystals to acetone or dichloromethane vapor results in the reformation of crystals of type A. The dimeric complexes in crystals of types A and B are all centrosymmetric and share a common ring conformation. Within these dimers, the coordination geometry of each gold center is planar with a P(2)Br donor set. In other respects, the Au(2)(µ-dppe)(2)Br(2) molecule is remarkably flexible and behaves as a molecular accordion, whose dimensions depend upon the solvate content of a particular crystalline phase. In particular, the dimer Au(2)(µ-dppe)(2)Br(2) is able to accommodate Au···Au separations that range from 3.8479(3) to 3.0943(2) Å, and these variations along with alterations in the Au-Br distances and in the P-Au-P angles are the likely causes of the differences in the luminescence properties of these crystals.

Crystalline Ge quantum dots embedded in SiO2 matrix synthesized by plasma immersion ion implantation.

A new plasma process, i.e. a combination of plasma immersion ion implantation and deposition (PIII&D) and high power impulse magnetron sputtering (HiPIMS), was developed to implant non-gaseous ions into material surfaces. The new process has the great advantage that thin film deposition and non-gaseous ion implantation can be achieved in a single plasma chamber. In this study, Ge ions were successfully implanted into SiO(2) thin film, which resulted in uniformly and homogeneously distributed crystalline Ge quantum dots (Ge-QDs) embedded in a SiO(2) matrix even without a further annealing process. Broader areas of application of PIII&D technology are envisaged with this newly developed process.

Temperature increase due to Joule heating in a nanostructured MgO-based magnetic tunnel junction over a wide current-pulse range.

The temperature increase due to Joule heating in a nanopillar of a magnetic tunnel junction sandwiched by top and bottom electrodes was calculated by the finite element method. The results for the critical condition for the current-induced magnetization switching measured over a wide current-pulse range were taken from the literature. At long pulse widths, the temperature increase was solely dependent on the magnitude of the critical current density. However, no saturation in the temperature increase occurred for short pulse widths. In this case, the temperature increase additionally depended on the pulse width, so that a broad maximum occurred in the pulse width (or the critical current density) dependence of the temperature increase. The original results for the critical condition were corrected by accounting for the temperature increase and these corrected results, together with the Slonczewski equation, were used to extract an accurate value for the thermal stability factor.

Switching windows for a nanostructured cell of synthetic ferrimagnets.

The magnetization switching window of nanostructured synthetic ferrimagnets with lateral dimension of 160 nm x 80 nm under combined in-plane magnetic fields along the longitudinal and transverse directions is investigated by numerical calculation using an analytical equation for the total energy. The considered total energy equation precisely accounts for the magnetostatic energy, which is significantly large in nanostructured magnetic cells. Due to the complex magnetization alignment of synthetic ferrimagnets, a different switching criterion based on the reversibility of magnetization process is used, instead of the simple criterion frequently used for single magnetic layers. Synthetic ferrimagnets with various thickness asymmetries are considered, and switching windows are calculated both in static and dynamic conditions. The static switching windows show a smaller dependence on the thickness asymmetry than the dynamic switching windows do. The dynamic switching window at a large thickness asymmetry resembles that of a single magnetic layer. The results are discussed in terms of energy profiles that can be obtained by locating the lowest energy path linking the two stable states from the total energy surface.

Perpendicular magnetic anisotropy properties of CoFeB/Pd multilayers.

The perpendicular magnetic anisotropy (PMA) properties of CoFeB/Pd multilayers are investigated as functions of the thickness of the constituent layers of the multilayers and of the substrate type. A relatively strong PMA is formed at small CoFeB thicknesses of 0.3 and 0.5 nm over the entire Pd thickness range of 0.47 to 1.26 nm. At a fixed CoFeB thickness, the PMA tends to increase with increasing Pd thickness and this behavior can be attributed to the fact that the interface tends to become flatter and smoother at a higher Pd thicknesss, leading to a stronger surface anisotropy. A stronger PMA is observed for the glass substrate than for the MgO substrate. Since the thermal stress formed at the CoFeB layer is tensile for both the glass and MgO substrates, the magnetoelastic interactions suggest the possibility of forming a Co-Pd alloy with a negative saturation magnetostriction at the CoFeB/Pd interfaces.

Internal jugular vein thrombosis associated with venous hypoplasia and protein S deficiency revealed by ultrasonography.

A 41-year-old woman, who had no thrombotic risk factors and past history except congenital scoliosis, underwent central venous catheterization (CVC) before correction of the scoliosis. When internal jugular vein (IJV) catheterization using the anatomical landmark technique failed, CVC under ultrasound guidance was tried. As a consequence, thrombosis and hypoplasia of the right IJV were incidentally detected by ultrasonography. Central venous catheters were then successfully placed in other veins under ultrasound guidance. Also, after examinations to rule out the possibility of pulmonary embolism and to clarify the causes of the IJV thrombosis, the patient was found to have protein S deficiency. CVC under ultrasound guidance should be recommended to prevent the failure of cannulation and complications such as thromboembolism in patients who could possibly have anomalies of vessels as a result of anatomical deformities caused by severe scoliosis, even if patients do not have thrombotic risk factors such as a history of central catheter insertion or intravenous drug abuse, cancer, advanced age, cerebral infarction, and left ventricular dysfunction. Also, if venous thrombosis is found in patients without predisposing risk factors, one should ascertain the cause of the hypercoagulable state, for example protein S deficiency, and perform appropriate treatment and prevention of venous thromboembolism.

Interfacial properties of [Pt/Co/Pt] trilayers probed through magnetometry.

The magnetic and interface properties of [Pt/Co/Pt] were investigated. First, the magnetic properties were determined from the magnetic dead layer plots, in which the Co layer was considered as two distinct parts representing different magnetic properties. The two parts with low and high tCo ranges are close to and away from the top interface (Co/Pt), respectively. The part close to the top interface shows a smaller magnetization (M) value and nonlinear behavior. However, the other part shows a higher M value closer to the bulk value and a linear behavior. The nonlinear behavior of the M values of the low tCo range was converted to an impurity level using simple assumptions. The results showed the effect of the top Pt layer on the magnetic properties of the Co layer. The results clearly demonstrate that magnetometry could be utilized as a means to understand the interface quality of magnetic multilayer systems.