Phase Diagram of the Neodymium Chloride-Sodium Chloride System

Differential thermal analysis was used to study the phase diagram of NdCl3-NaCl system. The peritectic reaction was found to occur at 540±7°C. The peritectic compound was confirmed to be Na3Nd5Cl18 by means of X-ray diffraction analysis. The homogeneity range Na3Nd5Cl18 could not be defined accurately, but appeared to be between 59 and 70 mol% of NdCl3 at temperatures between 300 and 540°C. This revised version was published online in July 2006 with corrections to the Cover Date.     

In-beam Mössbauer study of 57Fe using a secondary 57Mn beam and ion implantation

We have succeeded in obtaining well-resolved M?ssbauer spectra of ⁵⁷Fe arising from short-lived ⁵⁷Mn ( T _1/2 = 1.45 min) in Si and KMnO₄. The M?ssbauer spectra of ⁵⁷Fe in Si are well fitted with a curve consisting of two singlet lines, one being assigned as the interstitial Fe atoms and the other as substitutional ones. The relative intensities of the two lines infer that 60% of ⁵⁷Fe ( ←⁵⁷Mn) atoms land at the interstitial sites and 40% at the substitutional sites at temperatures between 30 K and 296 K. The result for the KMnO₄ sample suggests a presence of an exotic chemical species corresponding to a higher valence state than Fe^{6 +}. Received: 1 May 2001 / Accepted: 4 December 2001     

An improved method for the capillary gas chromatographic derivatization of polyhydroxylated steroids having tert-hydroxyl groups.

An improved method for a suitable derivatization of polyhydroxylated steroids having one or two tert-hydroxyl groups at the 5beta-, 14alpha-, 17alpha-, 24-, and/or 25-positions by capillary gas chromatography (CGC) is described. By using trimethylsilyl triflate as a silylating reagent and 2,6-lutidine as a catalyst, each of 5beta-cholane and 5alpha-cholestane series of steroids was successfully transformed into trimethylsilyl (TMS) ether derivatives to give a single CGC peak under mild conditions. More bulky triethylsilyl (TES) etherification of 14alpha- and 17alpha-hydroxy compounds provided multiple CGC peaks arising from completely- and/or incompletely-derivatized TES ethers accompanied by their thermal elimination products.     

Femtosecond depolarization dynamics of tris(8-hydroxyquinoline) aluminum films

For vapor-deposited tris(8-hydroxyquinoline) aluminum thin films, steady-state and subpicosecond transient optical anisotropy are investigated. It is found that the transient absorption anisotropy decays within tens of picoseconds. With a simple model calculation, the excited state population and anisotropy decay dynamics are disentangled, and the latter signal, the depolarization of the excited state, is explained by the energy transfer between the non-orthogonally-coordinated quinolate ligands. It is also shown that there are two pathways for this fast interligand energy transfer.     

Formation of benzylamines from triazene compounds via a 1,2-proton shift

A new approach to benzylamines using triazene compounds has been developed that is facilitated by the lithiation of aryltriazenes followed by treatment with an electrophile. The regioselectivity of the reaction can be controlled by means of the substituents in the aryl group. The reaction contains the following steps: intramolecular carbon-carbon bond formation involving lithiation of an alkyl group on a 3-nitrogen atom; a 1,2-proton shift; and the subsequent release of nitrogen gas. Through the use of a deuterated triazene, we were able to determine that the reaction proceeds through a 1,2-proton shift.     

Preparation of platinum complexes containing a thioamide-based SCS pincer ligand and their light emitting properties

Reaction of 1,3-bis(1-pyrrolidinothiocarbonyl)benzene with PtCl₂(PhCN)₂ afforded a platinum complex with η³-S,C,S type coordination. The molecular structure of the SCS-pincer platinum(II) complex was determined by X-ray analysis. Substitution of chloro ligand with anionic ligands such as iodo and acetylide was carried out. The complexes exhibit strong emission in a glassy frozen state as well as in the solid state. Light-emitting diodes based on the complexes displayed red electroluminescence.     

Study of Electron Beam Misalignment in a Submillimeter Wave Gyrotron

Electron beam misalignment in a submillimeter-wave gyrotron strongly affects its total efficiency as well as excitation of rotating and counterrotating modes. Some of misalignment phenomena were studied theoretically and experimentally.