title: Magnetic ordering in an organic polymer.
abstract: We describe preparation and magnetic properties of an organic pi-conjugated polymer with very large magnetic moment and magnetic order at low temperatures. The polymer is designed with a large density of cross-links and alternating connectivity of radical modules with unequal spin quantum numbers (S), macrocyclic S = 2 and, cross-linking S = (1/2) modules, which permits large net S values for either ferromagnetic or antiferromagnetic exchange couplings between the modules. In the highly cross-linked polymer, an effective magnetic moment corresponding to an average S of about 5000 and slow reorientation of the magnetization by a small magnetic field (less than or equal to 1 oersted) below a temperature of about 10 kelvin are found. Qualitatively, this magnetic behavior is comparable to that of insulating spin glasses and blocked superparamagnets.
authors.affiliation: Department of Chemistry, University of Nebraska, Lincoln, NE 68588-0304, USA. arajca1@unl.edu
authors.forename: A
authors.initials: A
authors.lastname: Rajca
authors.forename: J
authors.initials: J
authors.lastname: Wongsriratanakul
authors.forename: S
authors.initials: S
authors.lastname: Rajca