125510-51-2Relevant academic research and scientific papers
MAGNETIC COUPLING OF TWO TRIPLET PHENYLNITRENE UNITS JOINED THROUGH AN ACETYLENIC OR A DIACETYLENIC LINKAGE
Iwamura, Hiizu,Murata, Shigeru
, p. 33 - 48 (2007/10/02)
Some polymer radicals have been proposed as potential organic magnetic materials.In order to determine where to place the doublet or triplet centers on the side chains of a conjugated polymer chain, we have studied model dimers, i.e., isomeric bis(nitrenophenyl)acetylenes and diacetylenes.They were generated by photolyses of the corresponding diazides in MTHF at 10 K in an ESR cavity.The m,p'-dinitrenes showed strong fine-structure signals characteristic of quintet states that obeyed Curie law in the range 12-85 K.The m,m'-dinitrenes showed fine-structure signals due to quintet states that had the maximum intensities at 50 and 28 K for the mono- and diacetylenes, respectively.It is concluded that the two triplet centers at the m,p'- and m,m'-positions interact, respectively, ferro- and antiferromagnetically.Efforts directed to the construction of ferromagnetic poly(acetylenes) are briefly discussed.
