Premium
Synthesis, Structure, and Physical Properties of a Partial π‐Stacked Phenalenyl‐Based Neutral Radical Molecular Conductor
Author(s) -
Sarkar Arindam,
Itkis Mikhail E.,
Tham Fook S.,
Haddon Robert C.
Publication year - 2011
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201100730
Subject(s) - chemistry , radical , disproportionation , molecule , paramagnetism , valence (chemistry) , crystallography , crystal structure , condensed matter physics , organic chemistry , catalysis , physics
We report the synthesis, crystallization, and solid‐state characterization of the 3,7‐ethoxy‐substituted spirobiphenalenyl‐boron neutral radical 22 . The radical is distinguished by its low disproportionation energy and one‐dimensional structure. We show that our strategy of substitution of OEt group at the active positions of the phenalenyl units changes the crystal packing from its previously known OMe analogue and the solid‐state properties are dictated by the partial π‐stack structure and the oxygen atoms at the 3,7‐positions and can be best rationalized in terms of the resonating valence bond model. Magnetic susceptibility measurements show that in the solid state the radical remains paramagnetic but there is significant spin–spin interaction between the molecules. Band structure calculations reflect efficient overlap between the molecules along the π stack and show evidence of interactions between the spin‐bearing oxygen atoms. The room temperature electrical conductivity ( σ RT =2.0×10 −2 S cm −1 ) of 22 is higher than that observed in previously known one‐dimensional phenalenyl radicals.