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Gd3+ complexes have been shown to undergo unusual slow magnetic relaxation processes similar to those of single‐molecule magnets (SMMs), even though Gd3+ does not exhibit strong magnetic anisotropy. To reveal the origin of the slow magnetic relaxation of Gd3+ complexes, we have investigated the magnetic properties and heat capacities of two Gd3+‐phthalocyaninato triple‐decker complexes, one of which has intramolecular Gd3+–Gd3+ interactions and the other does not. It was found that the Gd3+–Gd3+ interactions accelerate the magnetic relaxation processes. In addition, magnetically diluted samples, prepared by doping a small amount of the Gd3+ complexes into a large amount of diamagnetic Y3+ complexes, underwent dual magnetic relaxation processes. A detailed dynamic magnetic analysis revealed that the coexistence of spin–lattice relaxation and phonon‐bottleneck processes is the origin of the dual magnetic relaxation processes. [ABSTRACT FROM AUTHOR]

The reaction of Fe(OAc)2 and Hbpypz with neutral TCNQ results in the formation of [Fe2(bpypz)2(TCNQ)2](TCNQ)2 (1), in which Hbpypz=3,5‐bis(2‐pyridyl)pyrazole and TCNQ=7,7′,8,8′‐tetracyano‐p‐quinodimethane. Crystal packing of 1 with uncoordinated TCNQ and π–π stacking of bpypz− ligands produces an extended two‐dimensional supramolecular coordination assembly. Temperature dependence of the dc magnetic susceptibility and heat capacity measurements indicate that 1 undergoes an abrupt spin crossover (SCO) with thermal spin transition temperatures of 339 and 337 K for the heating and cooling modes, respectively, resulting in a thermal hysteresis of 2 K. Remarkably, the temperature dependence of dc electrical transport exhibits a transition that coincides with thermal SCO, demonstrating the thermally induced magnetic and electrical bistability of 1, strongly correlating magnetism with electrical conductivity. This outstanding feature leads to thermally induced simultaneous switching of magnetism and electrical conductivity and a magnetoresistance effect. [ABSTRACT FROM AUTHOR]

A diamagnetic AuI4CoIII2 hexanuclear complex, [Au4Co2(dppe)2(l‐nmc)4]2+ ([1L‐nmc]2+; dppe=1,2‐bis(diphenylphosphino)ethane, l‐H2nmc=N‐methyl‐l‐cysteine), was newly synthesized by the reaction of [Co(l‐nmc)2]− with [Au2Cl2(dppe)] and crystallized with different inorganic anions (X=ClO4−, NO3−, Cl−, SO42−) to produce ionic solids ([1L‐nmc]Xn). Single‐crystal X‐ray analysis revealed that all the solids crystallize in the chiral space group F432 with a face‐centered‐cubic lattice structure consisting of supramolecular octahedra of complex cations. The paramagnetic nature of all the solids was evidenced by magnetic susceptibility measurements, showing the variation of the oxidation states of two cobalt centers in [1L‐nmc]n+ from CoII1.00CoIII1.00 for X=ClO4− or NO3− to CoII0.67CoIII1.33 for X=Cl−, via CoII0.83CoIII1.17 for X=SO42−. The difference in the CoII/III mixed‐valences was explained by the difference in sizes and charges of counter anions accommodated in lattice interstices with a fixed volume. [ABSTRACT FROM AUTHOR]

Abstract: A bis(μ‐oxido)dinickel(III) complex was synthesized and characterized by single crystal X‐ray diffraction, resonance Raman, and ESI‐mass measurements. Magnetic susceptibility measurements by SQUID and EPR spectroscopy reveal that the complex has a triplet ground state, which is unprecedented for high‐valent metal (M) complexes with [M2(μ‐O)2] diamond core. DFT studies indicate ferromagnetic coupling of the nickel(III) centers. The complex exhibits hydrogen abstraction reactivity and oxygenation reactivity toward external substrates. [ABSTRACT FROM AUTHOR]

The development of magnetic molecules with long spin reversal/decoherence times highly depends on the understanding of relaxation behavior under different external conditions. Herein, a magnetic study on a RuIII complex ( 1) is presented. Detailed analysis of the relaxation time and the magneto-heat capacity data suggests that the resonant phonon trapping process dominates the magnetic relaxation in the crystalline sample of 1, slowing down the spin relaxation rate, as further confirmed by the measurements on a ground sample and frozen solution. Thus, it provides a rare example showing that 4d metal-centered mononuclear compounds without second-order anisotropy can display slow magnetic relaxation. [ABSTRACT FROM AUTHOR]

Here we report the synthesis, structure and detailed characterisation of three n-membered oxovanadium rings, Na n[(V=O) nNa n(H2O) n(α, β, or γ-CD)2]⋅ m H2O ( n=6, 7, or 8), prepared by the reactions of (V=O)SO4⋅ x H2O with α, β, or γ-cyclodextrins (CDs) and NaOH in water. Their alternating heterometallic vanadium/sodium cyclic core structures were sandwiched between two CD moieties such that O-Na-O groups separated the neighbouring vanadyl ions. Antiferromagnetic interactions between the S=1/2 vanadyl ions led to S=0 ground states for the even-membered rings, but to two quasi-degenerate S=1/2 states for the spin-frustrated heptanuclear cluster. [ABSTRACT FROM AUTHOR]

After more than three decades of molecular and carbon-based electronics, the creation of air- and thermally stable n-type materials remains a challenge in the development of future p/n junction devices such as solar cells and thermoelectric modules. Here a series of ordinary salts are reported such as sodium chloride (NaCl), sodium hydroxide (NaOH), and potassium hydroxide (KOH) with crown ethers as new doping reagents for converting single-walled carbon nanotubes to stable n-type materials. Thermoelectric analyses reveal that these new n-type single-walled carbon nanotubes display remarkable air stability even at 100 °C for more than 1 month. Their thermoelectric properties with a dimensionless figure-of-merit (ZT) of 0.1 make these new n-type single-walled carbon nanotubes a most promising candidate for future n-type carbon-based thermoelectric materials. [ABSTRACT FROM AUTHOR]

Heterometallic Prussian blue analogues are known to exhibit thermally induced charge transfer, resulting in switching of optical and magnetic properties. However, charge-transfer phase transitions have not been reported for the simplest FeFe cyanide-bridged systems. A mixed-valence FeII/FeIII cyanide-bridged coordination polymer, {[Fe(Tp)(CN)3]2Fe(bpe)⋅5 H2O} n, which demonstrates a thermally induced charge-transfer phase transition, is described. As a result of the charge transfer during this phase transition, the high-spin state of the whole system does not change to a low-spin state. This result is in contrast to FeCo cyanide-bridged systems that exhibit charge-transfer-induced spin transitions. [ABSTRACT FROM AUTHOR]

A newly synthesized one-dimensional (1D) hydrogen-bonded (H-bonded) rhodium(II)-η5-semiquinone complex, [Cp*Rh(η5- p-HSQ-Me4)]PF6 ([ 1]PF6; Cp*=1,2,3,4,5-pentamethylcyclopentadienyl; HSQ=semiquinone) exhibits a paraelectric-antiferroelectric second-order phase transition at 237.1 K. Neutron and X-ray crystal structure analyses reveal that the H-bonded proton is disordered over two sites in the room-temperature (RT) phase. The phase transition would arise from this proton disorder together with rotation or libration of the Cp* ring and PF6− ion. The relative permittivity εb′ along the H-bonded chains reaches relatively high values (ca., 130) in the RT phase. The temperature dependence of 13C CP/MAS NMR spectra demonstrates that the proton is dynamically disordered in the RT phase and that the proton exchange has already occurred in the low-temperature (LT) phase. Rate constants for the proton exchange are estimated to be 10−4-10−6 s in the temperature range of 240-270 K. DFT calculations predict that the protonation/deprotonation of [ 1]+ leads to interesting hapticity changes of the semiquinone ligand accompanied by reduction/oxidation by the π-bonded rhodium fragment, producing the stable η6-hydroquinone complex, [Cp*Rh3+(η6- p-H2Q-Me4)]2+ ([ 2]2+), and η4-benzoquinone complex, [Cp*Rh+(η4- p-BQ-Me4)] ([ 3]), respectively. Possible mechanisms leading to the dielectric response are discussed on the basis of the migration of the protonic solitons comprising of [ 2]2+ and [ 3], which would be generated in the H-bonded chain. [ABSTRACT FROM AUTHOR]

This paper describes a self-calibrating A/D converter (ADC), which continuously obtains calibration data for the error of circuit elements and carries out self-calibration using these data in A/D conversion. This ADC is able to maintain a highly accurate conversion for a long time by renewing the calibration data continuously. By subdividing the calibrating operation and distributing the operation among the conversions, a lowering of conversion speed which is due to the calibrating operation can be reduced. On the assumption that the calibration data are destroyed or circuit parameters are varied by drift, conventional self-calibrating ADC and this ADC are simulated and experiments are carried out by breadboard circuit. Consequently, it is verified that the conventional self-calibrating ADC is not capable of maintaining highly accurate conversion for data destruction and drift. On the other hand, the continuously self-calibrating ADC is able to recover the conversion accuracy after several tens conversion cycles for data destruction and maintain highly accurate conversion against variation of circuit parameters due to drift. [ABSTRACT FROM AUTHOR]

B Thermally-induced simultaneous switching b of magnetism and electrical conductivity has been realized by a two-dimensional supramolecular coordination assembly composed of Fe SP II sp spin-crossover complexes and partially charged TCNQ (7,7',8,8'-tetracyano- I p i -quinodimethane) radicals. B Thermally-induced simultaneous switching b of magnetism and electrical conductivity has been realized by a two-dimensional supramolecular coordination assembly composed of Fe SP II sp spin-crossover complexes and partially charged TCNQ (7,7',8,8'-tetracyano- I p i -quinodimethane) radicals. Fe SP II sp spin-crossover units are directly linked to -stacked TCNQ columns, thus possessing strongly coupled magnetism (from localized d electrons) and electrical conductivity (from delocalized electrons). [Extracted from the article]

Cyclodextrin ligands were shown to act as supports for the synthesis of a family of six‐, seven‐, and eight‐membered oxovanadium ring complexes. The three complexes gave a perfect opportunity to probe the magnetic ground states of even‐ and odd‐membered antiferromagnetically coupled homospin ring systems. The seven‐membered ring is an extremely rare example of a real spin Möbius strip, and provides the focus of the cover art, in which its structural silhouette and magnetization plots are overlaid by another heptagonal anomaly: a UK 50 pence piece. More information can be found in the Full Paper by H. Oshio et al. on page 14205 ff. [ABSTRACT FROM AUTHOR]

Y. Nonoguchi, T. Kawai, and co‐workers prepare high‐stability carbon nanotube structures that behave as n‐type conductors on page 3021. Single‐walled carbon nanotubes are converted to n‐type conductors by doping with salt‐crown ether complexes. The material demonstrates unprecedented durability in air even at raised temperatures, an essential requirement in thermoelectric applications. [ABSTRACT FROM AUTHOR]

Electromotive force of galvanic cells with zirconia solid electrolytes was measured to determine the activity of gallium in liquid Ga-In-Te alloys in the temperature range of 1000 to 1200 K along 3 psuedobinary lines of (In[sub y]Te[sub 1-y])-Ga where y = 0.25, 0.50 and 0.75. The mixture of Ga and Ga[sub 2]O[sub 3] was used as a reference electrode. The activity curves of Ga are very complicated at 1073 K. Isoactivity curves at 1073 K in the ternary Ga-In-Te alloys were derived by combining the activity data of Ga-In and Ga-Te alloys. Using Darken's equation, 2 binary data of Ga-In and Ga-Te and ternary data in this study, ΔG[sup xs] at 1073 K were derived. The results were compared with those from 3 model calculations proposed by Toop, Kohler and Chou to show better agreement between the experimental values and those by Toop's and Chou's models. [ABSTRACT FROM AUTHOR]