2496-16-4Relevant academic research and scientific papers
New U-shaped liquid crystals azobenzene derived from catechol for photoswitching properties
Rahman, Md. Lutfor,Biswas, Tapan Kumar,Sarkar, Shaheen M.,Yusoff, Mashitah Mohd,Abdul Malek, Muhammad Nor Fazli,Tschierske, Carsten
, p. 125 - 133 (2015)
A new series of liquid crystals whose molecular structure consists of a U-shaped unit as a central core and two rod-like azobenzenes as the peripheral units are synthesized. The mesomorphic properties were investigated by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction. The existence of nematic and smectic A phase was confirmed by textures and X-ray diffraction. The trans-form of azo compounds showed a strong band in the UV region at ～365 nm for the π-π? transition, and a weak band in the visible region at ～450 nm due to the n -π? transition. These molecules exhibit a strong photoisomerization behavior in which trans-cis take 50 and 55 s for compounds L4/5 and L4/6, respectively, whereas cis-trans take place almost 29 and 30 h, respectively. Long thermal back relaxation allows us to realize that optical storage devices with these materials which need longer periods.
Synthesis of new spin probes based on aminoaryl-substituted imidazoline nitroxides
Reznikov, V. A.,Berezina, T. A.,Kirilyuk, I. A.,Volodarskii, L. B.
, p. 424 - 427 (2007/10/02)
A series of new spin probes, azides and isothiocyanates, were synthesized starting from aminoaryl-substituted nitroxides which are derivatives of 3-imidazoline and 3-imidazoline-3-oxide.The new compounds were transformed to complexones, derivatives of iminodiacetic acid. - Key words: nitroxyl radical; azides; isothiocyanates; spin probes; diazonium salts.
