Novel BEDT-TTF salts with magnetic anions MoOCl/sub 4/(H/sub 2/O)]- and [Re/sub 2/(NCS)10]/sup 3-/: structure and properties

Abstract

Summary form only given. We report two novel structural phases of BEDT-TTF (ET) salts containing magnetic transition metal anions. Both compounds are unusual in not containing discrete layers of anions and cations. ET[MoOCl/sub 4/(H/sub 2/O)] is triclinic, P1, a=6.174, b=8.989, c=10.103/spl Aring/, /spl alpha/=71.95, /spl beta/=79.24, /spl gamma/=83.77/spl deg/, Z=l. Intensity distribution indicates a centrosymmetric structure with the MoOCl/sub 4/(H/sub 2/O)]- anion disordered at an inversion centre. The anions form hydrogen-bonded chains that lie in between sheets of edge-linked ET molecules. The compound is semiconducting, with E/sub A/ /spl tilde/ 0.1ev. ET/sub 3[Re/sub 2/(NCS)/sub 10/].CH/sub 2/Cl/sub 2/ is triclinic, P1, a=12.185, b=13.251, c=14.772/spl Aring/, /spl alpha/=63.69, /spl beta/=86.56, /spl gamma/=64.50/spl deg/, Z=l. Structural features include a disordered ET molecule, with half occupation on two sites related by inversion. Examination of sulfur-sulfur distances indicates no continuous network between ET molecules, rather these interactions are primarily seen between ET and the nitrogen-bonded [Re/sub 2/(NCS)/sub 10]/sup 3-/ anion. The compound is semiconducting, with E/sub A/=0.30eV.