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Information × Registration Number 0209U006046, 0106U003101 , R & D reports Title Highly anisotropic conductors, superconductors and magnetics based on the sulfur - and vitrogencantaining compounds. popup.stage_title Head Starodyb Vladimir Aleksandrovich, Registration Date 20-01-2009 Organization Kharkov national university named after V.N. Karazin popup.description2 Objects of research: New anion-radical salts (ARS) of tetracyanoquinodimethane TCNQ with pyrazine derivatives based cations. The purpose of work: Receipt of conducting ARS TCNQ with pyrazine derivatives based cations. Revealing of peculiarities of the influence of quantity, arrangement and type of substituents in the cations on structure, optical, electrophysical and magnetic properties of ARS TCNQ. Investigations of the possibility to raise the dimensionality of these proerties of ARS by changing cation structure. Methods: modern methods of synthesis, IR-, UV-, Raman spectroscopy, electroconductivity and magnetic susceptibility measurements, X-ray analysis.The received results and novelty: 11 new complex ARS TCNQ has been obtained. IR spectra of the synthesized compounds were investigated and forbidden gap was estimated. It is shown, that most of the ontained compounds are narrow band semicondctors. Temperature dependence of electroresistance was investigated. Data of the measurements reveals the semiconductor nature for 8 ARS and metallic conductivity for [N-Me-Pz]TCNQ2 (down to 120К). X-ray analysis was done for 6 synthesized salts. It revealed strong interstack interactions in TCNQ columns, these interactions may raise dimensionality of optical, electrophysical and magnetic properties of salts. It is shown, that some of synthesized ARS has unusual layered structure. Magnetic properties of N-Me-2,5-Me2-PzI and N-Me-2,3-Me2-PzI are investigated. Most significant structure changes appears with changing pyrazine-based cations to pyrazine derivatives-based ones. Revealed that next changes in amount, arrangement and type of substituent in the cations don't has an effect on the packing of TCNQ particles. The presense of significant interstack interactions and spin coupling character are approved. Spin coupling character is according to the spin-ladder type of the ordering. Scope: multifunctional materials for electronic technics, spintronics, materials for sensor electronics and pH-metry electrodes. Product Description popup.authors popup.nrat_date 2020-04-02 Close