Mechano-responsive circularly polarized luminescence of organic solid-state chiral emitters. Issue 3 (9th November 2018)

• Record Type: Journal Article
• Authors: Louis, Marine; Sethy, Ramarani; Kumar, Jatish; Katao, Shouhei; Guillot, Régis; Nakashima, Takuya; Allain, Clémence; Kawai, Tsuyoshi; Métivier, Rémi
• Is Part Of: Chemical science. Volume 10:Issue 3(2019)
• Page Start: 843
• Page End: 847
• Publication Date: 2018-11-09
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c8sc04026e
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : Mechano-CPL effect: chiral difluoro-boron β-diketonate complexes show concomitant changes of emission color as well as solid state chiroptical properties upon mechanical stimulation. Abstract : Two difluoro-boron β-diketonate complexes bearing chiral amido groups have been synthesized. Their mechano-responsive luminescence and chiroptical properties have been investigated in the solid state. Both compounds display a bright blue-green emission and a significant circularly polarized luminescence (CPL) signal in the crystalline state, with | g lum | values as high as 2.2–2.4 × 10 −2 . A bathochromic shift in emission, together with a decrease of | g lum | values to c.a. 3 × 10 −3, is induced upon application of a shearing stress. For theDFB-Hex-amide compound, interestingly, sign inversion of the anisotropy factor g lum is observed under mechanical stimulation ("mechano-CPL effect"), which can be rationalized by a switching between monomer and excimer emission.