A new family of two-dimensional metal coordination polymers with the general formula [M(ox)(bpy)] (M = Fe(II), Co(II), Ni(II), Zn(II); ox C2O42-; bpy 4,4'-bipyridine) have been designed and synthesized via hydrothermal routes. Quantitative yields were obtained in all cases. The title compounds [Fe(ox)(bpy)] (I), [Co(ox)(bpy)] (II), [Ni(ox)(bpy)] (III), [Zn(ox)(bpy)] (IV) represent first network structure constructed by bridging oxalate 4,4'-bpy mixed ligands. I−IV are isostructural belong to...

We report here an entirely new phenomenon, namely magnetic-field-induced superconductivity in Ce${\mathrm{Pb}}_{3}$, a system which at zero field is heavy-fermion antiferromagnet. This phenomenon novel several respects. It the first reported superconductor. also superconductor that Moreover, it has simplest crystal structure, ${\mathrm{Cu}}_{3}$Au, of any known or

Two-dimensional transition-metal coordination polymers [MCl2(bpy)] (M = Fe, Co, Ni; Co/Ni, bpy 4, 4'-bipyridine) have been synthesized in superheated water solutions. The hydrothermal routes resulted four compounds [FeCl2(bpy)](I), [CoCl2(bpy)](II), [NiCl2(bpy)](III), and [(Co/Ni)Cl2(bpy)](IV). Compounds I−IV are isostructural belong to orthorhombic crystal system, space group Cmmm (No. 65). Crystal data for I: a 11.929(2) Å, b 11.447(2) c 3.638(1) V 496.77(18) Å3, Z 2. II: 11.993(2)...

Nanomaterials that make use of both electron charge and spin are highly desirable extremely attractive in the development new multifunctional devices for optoelectronics information storage technology. In this study, we demonstrate hybrid nanostructures Zn1-xMnxSe(L)0.5 (L = ethylenediamine, 1,3-propanediamine) can be assembled with substitution Zn Mn ZnSe(L)0.5 systems. The latter composed perfectly ordered ZnSe semiconductor nanolayers interconnected via organic molecules coordinately...

The effect of carrier concentration on fulleride superconductivity is studied by x ray, Raman, magnetization, and ESR two new cubic families: ${\mathrm{Na}}_{2}{\mathrm{Cs}}_{x}{\mathrm{C}}_{60}$ $(0<x<1)$ ${M}_{3\ensuremath{-}y}{\mathrm{Ba}}_{y}{\mathrm{C}}_{60}$ ( $0.2<y<2$, $M\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\mathrm{K}$, Rb, or Cs). These are isostructural with known $\mathrm{Pa}\overline{3}$ $\mathrm{Fm}\overline{3}m$ trivalent superconductors, respectively, but...

Measurements of the temperature and concentration dependence specific heat, magnetic susceptibility, electrical resistivity for ${\mathrm{Ce}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{La}}_{\mathrm{x}}$${\mathrm{Pb}}_{3}$ are presented. The data scale with Ce ions over surprisingly large intervals x T. low-temperature heat per ion agrees quantitatively that an S=(1/2) Kondo impurity ${T}_{K}$apeq23.3 K. These results strongly suggest intersite correlations do not play expected...

The effect of orientational order on fulleride superconductivity was studied by performing DC SQUID magnetometry and high-resolution x-ray diffraction the title quaternary phases. These are all simple cubic, Pa3space group, with same molecular as occurs in pure C60. Tc vs. lattice constant correlation is much steeper than found for merohedrally-disordered Fm3m phases, implying possibility large enhancements only minor additional dilation sc lattice. can be rationalized primarily due to a...

Multiwall carbon nanotubes were studied by dc magnetization and electron spin resonance (ESR) measurements. Hole doping is inferred from both the high-field susceptibility ESR parameters complying favorably with band model of two-dimensional graphite. Paramagnetic deviations are evinced on diamagnetic at weak fields low temperatures, conforming qualitatively Aharonov-Bohm effect energy gap for magnetic field parallel to tube axis. Comparison theoretical predictions ensembles reveals...

The temperature dependence of the relative recoil-free fraction $^{119}\mathrm{Sn}$ M\"ossbauer absorption has been measured in orthorhombic superconducting and tetragonal nonsuperconducting phase doped ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$. For ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ phase, shows softening which appears for T&lt;150 K, whereas it agrees...

The electronic properties of single-wall carbon nanotubes (SWNTs) have been studied using dc magnetization and electron spin resonance (ESR). displays a weak diamagnetic susceptibility $\ensuremath{\approx}{10}^{\ensuremath{-}7}\phantom{\rule{0.3em}{0ex}}\mathrm{emu}∕\mathrm{g}$. ESR measurements reveal narrow line low intensity metallic shape. shows major Pauli contribution at high temperatures $(T>150\phantom{\rule{0.3em}{0ex}}\mathrm{K})$ an appreciable Curie component lower temperatures....

UNiSn, as well certain other ternary actinide compounds, displays very anomalous behavior in the temperature dependence of electrical resistivity, ρ(T). In UNiSn this unusual ρ(T) has been attributed to half-metallic with a semiconducting gap minority spin band and metallic majority ferromagnetic transition vicinity 50 K. We have studied using 119Sn Mössbauer spectroscopy observed that annealing procedures influence microscopic properties sample profound way. As-cast samples are nonmagnetic....

The temperature and field dependence of the magnetization have been measured to investigate magnetic properties first oxalate–bpy mixed-ligand framework with a general formula M(ox)(bpy) (M = Fe(II), Co(II), Ni(II); ox C2O42−; bpy 4,4′-bipyridine). All compounds in system crystallize an orthorhombic structure space group Immm (No. 71), which M ions form one-dimensional chains along axis. Spontaneous orderings transition temperatures 12, 13, 26 K found for Fe(ox)(bpy), Co(ox)(bpy),...

The temperature dependence of the magnetic susceptibility, low-temperature specific heat, and field high-field magnetization were measured for pseudobinary system $\mathrm{U}{({\mathrm{In}}_{1\ensuremath{-}x}{\mathrm{Sn}}_{x})}_{3}$ $0\ensuremath{\le}x\ensuremath{\le}1$. results show a clear evolution from long-range antiferromagnetism $x&lt;0.45$ (In rich) to heavy-fermion region $0.45\ensuremath{\le}x\ensuremath{\le}0.80$ highly enhanced paramagnetism $x&gt;0.8$ (Sn rich). These represent...

A three-dimensional coordination polymer, [Mn3(OH)2Na2(3-cnba)6]n (1) (3-Hcnba = 3-cyanobenzoic acid), has been synthesized by the reaction of MnCl2, NaN3, and 3-Hcnba in water. Its crystal structure was determined single-crystal X-ray diffraction. Magnetic studies show that complex behaves as a metamagnet built from effective ferrimagnetic Mn(II) chains which spin moments are linked interactions an AF-F-AF (F ferromagnetic AF antiferromagnetic) sequence triangular magnetic repeating unit.

The magnetic to nonmagnetic transition in actinide alloys and intermetallic compounds is attributable the delocalization of 5f electrons due an increase f-f overlap and/or f-spd hybridization. USn3 paramagnetic at all temperatures appears be very near border between behavior. In contrast, UPb3 has antiferromagnetic 31 K appear highly localized. Both these systems have sufficiently large U-U separations expect that hybridization major contributing factor electrons. room temperature lattice...

Abstract The phase stability of HfV2-based C15 Laves phases has been studied by specific heat measurements and in-situ transmission electron microscopy at low temperatures. results indicate that HfV2 undergoes a structural transformation approximately 115 K Nb additions reduce the temperature, eventually stabilizing structure. First-principles quantum-mechanical calculations based on local-density functional theory have performed to study electronic structure physical properties MV2 (M = Zr,...

The electronic properties of boron-doped multiwall carbon nanotubes (MWNTs) have been studied using static magnetization and electron spin resonance. A relatively strong ferromagnetic signal has identified in the dc response that shows occurrence ferromagnetism, coexisting with orbital magnetism conduction electrons. small diamagnetic susceptibility weak temperature variation $g$ factor, which is observed narrow conduction-electron resonance (CESR), indicate a Fermi level shift...

Seven new polyketides named fusarisolins F-K (1-6) and fusarin I (7) were isolated from the marine-derived fungus Fusarium solani 8388, together with known anhydrojavanicin (8), 5-deoxybostry coidin (9), scytalol A (10). Their structures established by comprehensive spectroscopic data analyses, comparison of 1H 13C NMR those reported in literature. Fusarisolin F (1) contained both a dichlorobenzene group an ethylene oxide unit, which was rare nature. In bioassays, fusarisolin (4), J (5), (9)...

Monomethylamine is employed as a solvent for the preparation of alkali-metal (K, Rb, Cs and mixtures) doped [60]fullerene (C60). Not only initial solution homogeneous, but also extended temperature range this solvent, compared to ammonia, provides favourable conditions single phase, well defined materials with high superconducting volume fractions. The were characterized by dc magnetization X-ray diffraction measurements.

The temperature dependence of the specific heat shows that strong electron-phonon coupling system HfV2 undergoes a structural transformation at 116 K and becomes superconducting around 9 K. instability can be interpreted in terms Fermi surface nesting. shifts to lower temperatures with very dilute Nb substitution HfV2, completely disappears only 5 at. % Nb. low-temperature large density states level. These experimental results are consistent predictions from band-structure calculations.

A new class of fullerides, M${\mathrm{Ba}}_{2}$${\mathrm{C}}_{60}$ (M=K, Rb, or Cs) and M${\mathrm{BaCsC}}_{60}$, allows us to study the effect molecular valence on electronic structure while maintaining crystal ${\mathit{M}}_{3}$${\mathrm{C}}_{60}$ superconductors. X-ray diffraction Raman scattering show that these are face-centered cubic with pentavalent quadrivalent ${\mathrm{C}}_{60}$'s, respectively. We find no evidence for superconductivity down 0.5 K, electron spin resonance indicates...

CrCl3 has been known for a long time to be quasi-2D ferromagnet (FM) with specific-heat peak at 16.8K. Its 3D ordering is antiferromagnetic (AFM) alternating 2D FM sheets perpendicular the c-axis. Kuhlow [Phys. Stat. Sol. A 72, 161 (1982)] carried out Faraday rotation measurements on and concluded, fairly tenuous grounds, that there are actually two closely spaced magnetic transitions, one “16.7K” which of in-plane spins start ordering, but do so random alignment relative c-axis (the latter...