Structural transition and pair formation in Fe3O2BO3 - art. no. 147201

We observe for the first time a structural phase transition in the oxyborat e Fe3O2BO3 which occurs along three leg ladders present in this material. X -ray diffraction shows that this transition at 283 K is associated with a n ew phase where atomic displacements occur in alternate directions perpendic ular to the axis and within the plane of the ladders. Magnetic data show th at these displacements lead to the formation of singlet pairs which dissoci ate close to the structural transition. Anomalies in the transport properti es also occur close to 283 K showing that the structural transition is rela ted to a charge ordering phenomenon in a low dimensional structure.