We have studied local structure of IrTe2 by Ir L-3-edge extended x-ray absorption fine structure (EXAFS) measurements as a function of temperature to investigate origin of the observed structural phase transition at T-s similar to 270 K. The EXAFS results show an appearance of longer Ir-Te bond length (Delta R similar to 0.05 angstrom) at T < T-s. We have found Ir-Ir dimerization, characterized by distinct Ir-Ir bond lengths (Delta R similar to 0.13 angstrom), existing both above and below T-s. The results suggest that the phase transition in IrTe2 should be an order-disorder-like transition of Ir-Ir dimers assisted by Ir-Te bond correlations, thus indicating important role of the interaction between the Ir 5d and Te 5p orbitals in this transition.
B., J., M., B., L., S., Maugeri, L., S., P., K., K., et al. (2013). Local structural displacements across the structural phase transition in IrTe 2: Order-disorder of dimers and role of Ir-Te correlations. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 88(22) [10.1103/physrevb.88.224109].
Local structural displacements across the structural phase transition in IrTe 2: Order-disorder of dimers and role of Ir-Te correlations
MAUGERI, LAURA;
2013-01-01
Abstract
We have studied local structure of IrTe2 by Ir L-3-edge extended x-ray absorption fine structure (EXAFS) measurements as a function of temperature to investigate origin of the observed structural phase transition at T-s similar to 270 K. The EXAFS results show an appearance of longer Ir-Te bond length (Delta R similar to 0.05 angstrom) at T < T-s. We have found Ir-Ir dimerization, characterized by distinct Ir-Ir bond lengths (Delta R similar to 0.13 angstrom), existing both above and below T-s. The results suggest that the phase transition in IrTe2 should be an order-disorder-like transition of Ir-Ir dimers assisted by Ir-Te bond correlations, thus indicating important role of the interaction between the Ir 5d and Te 5p orbitals in this transition.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
