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Title: Helicene‐Bis‐Porphyrin Conjugates: Exciton Coupling Chirality and Chiral‐Induced Spin Selectivity
Following previous work on helicene–porphyrin conjugates in which carbo[6]helicene are connected to zinc‐porphyrin via phenyl‐bis‐ethynyl bridges (Por(Zn)‐H[6]1, series 1), and displaying clear exciton coupling (EC) chirality, novel carbo[6]helicenes derivatives substituted at their 2,15 positions by zinc‐porphyrin units are prepared, either through a triple bond (Por(Zn)‐H[6]2, series 2), or through an alkynyl‐phenyl bridge (Por(Zn)‐H[6]3, series 3). Series 2 is also synthesized with free porphyrins or different metals [Ni(II) and Pd(II)]. Their photophysical and chiroptical properties (electronic circular dichroism and circularly polarized luminescence) are characterized, and it is examined how i) the distance between the porphyrin units and ii) the metal type impacted these properties. Experimental and theoretical analyses highlight strong responses originating from EC chirality in combination with the typical helicene‐centered optical activity. ThePor(Zn)‐H[6]2system displaying strong absorption dissymmetry factors is then selected to experimentally examine the chiral‐induced spin selectivity effect by magnetic conductive atomic force microscopy; a spin polarization of 50% is measured.  more » « less
Award ID(s):
2503332
PAR ID:
10664095
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley
Date Published:
Journal Name:
ChemistryEurope
Volume:
4
Issue:
1
ISSN:
2751-4765
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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