Molecular design of organic ferrimagnets

摘要

Two kinds of molecular design for genuinely organic molecule-based ferrimagnetics are reported. (I) The coulombic interaction between an anion and a cation is utilised for co-crystallizing organic radical molecules with different spin quantum numbers. This is referred to "organic salt ferrimagnetics". A phenol derivative of nitronyl nitroxide #pi#-biradical with S=1 has been synthesised as an anionic component of the salt and the electronic spin structure characterized. (II) The phenolic #pi#-biradical with S=1 and a carboxyl-substituted #pi#-radicals with S=1/2 have been esterified to give model compounds for "single-component ferrimagnetics". Potentialities of the model compounds as building blocks of molecule-based ferrimagnetics have been examined by susceptibility and ESR measurements.