Magnetic Bistability in the Crystaline Fullerene Radical Salt

Compounds with magnetic bistability is highly attractive for the construction of switches,thermal sensors,information-storage media and memory devices.Herein,we report a crystalline fullerene radical anion salt[Na(THF)_(5)]C_(60)(1),obtained by the reduction of C_(60) with Na in solution,which exhibits magnetic bistability accompanied with one magnetostructural transition,giving low temperature(LT),high temperature(HT)phases and a metastable phase.

Ferromagnetic Exchange Coupling in Ni(Ⅱ)Complexes with a Coordinated Boron-Oxamido Radical:A Result of Spin State Transition

A Ni(Ⅱ)coordination complex 1 with a novel boron-oxamido radical ligand was synthesized and isolated.Reactions of 1 with N,N-dimethyl-4-pyridinamine(DMAP)and 4,4'-bpy resulted in 2 and 3,respectively,accompanied by the spin state transition from S=1/2 to S=3/2.Both 2 and 3 were isolated as stable crystals and characterized to feature an S=3/2 spin state,with the S=1 Ni(Ⅱ)atoms ferromagnetically coupled with the ligand-centred radicals,by SQUID measurement and EPR spectroscopy.Complex 3 represents the first example of one-dimensional magnetic chain constructed by S=3/2 Ni(Ⅱ)-radical units.

Stable Boron-Containing Blue-Photoluminescent Radicals

It is highly urgent to develop synthetic strategies to make new category of stable luminescent radicals with desired emission wavelength.In this study,we have isolated two dioxoborocyclic radicals(3 and 4)by a direct synthetic route.They were characterized by UV,EPR spectroscopy and SQUID measurements.Their structures were obtained by single-crystal X-ray diffraction.Both radicals produce blue-photoluminescence(458 nm for 3 and 478 nm for 4)by radiative decay from higher excited states(D_(2)/D_(3))to the ground state(D_(0))based on theoretical calculation,breaking Kasha rule.The work records a new kind of radical emitters and the first stable radicals with blue emission bands.

Room-Temperature Reversibleσ-Dimerization of a Phenalenyl Radical

Phenalenyl derivatives have been of tremendous interest due to their reversible dimerization in response to the external stimuli such as temperature.However,most of PLY derivatives only show the reversibility dependent on temperature.Herein,we report a unique PLY-based radical anionic salt with reversibleσ-dimerization controlled by solvent rather than temperature.The structure and reversibility of this PLY anion system have been spectroscopically,crystallographically,and theoretically investigated.The molecule exists mainly as theσ-dimer form of K2[σ-12]in toluene,while it can be broken into the monomeric radical anion 1•–by re-dissolving in THF.Moreover,when THF is replaced with toluene,radical 1•–could beσ-dimerized back again.Theoretical calculations reveal that the potassium ions are necessary for the formation of theσ-dimer and the solvent polarity controls theσ-dimerization by regulating the presence of K+.

Zig-Zag Diphosphene Oligomers Linked by Silver(Ⅰ)Cation

Summary of main observation and conclusion The coordination of silver cation to dlphosphene Mes"P=PMes"(1,Mes*=tBu3C6H2)was investigated in detail.The reaction of 1 with Ag(Al(ORF)4)(ORF=OC[CF3]3)in the ratios of 2:1,3:2 and 1:2 led to the formation of the first cationic silver linked diphos-phene complexes 2-4.Complexes 2 and 3 contain two and three diphosphene molecules linked by the linear Ag(Ⅰ)cation,respectively,and they feature unusual zig-ag topologies.Complex 4 is a dinuclear silver complex,and each Ag(Ⅰ)center features a tetrahedral geometry,coordinated by one phospho-rus atom of diphosphene 1 and three chloro atoms of two CH2Cl molecules.