Neutron Diffraction Study of the Extent of Disorder in the Low Temperature (20 K) Structure of beta -(BEDT-TTF) Sub 2 I sub 2 Br

摘要

The structure of beta -(BEDT-TTF) sub 2 I sub 2 Br at 20 K has been determined from single crystal time-of-flight neutron diffraction data. The (I-I-Br) sup - anion remains disordered and the BEDT-TTF, or ''ET'', molecules (including the terminal ethylene groups) remain ordered at low temperature. This indicates that disorder in the anion alone appears sufficient to suppress superconductivity as observed in electrical properties measurements. 7 refs. 2 figs. (ERA citation 11:051527)