Abstract
The title compound crystallizes in the orthorhombic space group P2l212l, Z = 4, with a = 11.707 (4) Á, b = 12.038 (4) Á, and c = 18.308 (7) Á. The structure consists of discrete linear arrays of alternating [Fe(bpy)2Cl2]+ cations and [FeCl4]" anions located at intervals of ~c/2 in the unit cell. The shortest interionic contact (Cl-C) is 3.39 A. The [Fe(bpy)2Cl2]+ ion forms a distorted octahedron with the two chlorine atoms in a cis arrangement. A significant lengthening is observed for those Fe-N distances trans to Cl (average 2.193 (7) A; Fe-N cis to Cl average 2.121 (9) A). The [FeCl4]" ion displays the expected tetrahedral geometry with Fe-Cl = 2.184 (2) A. Low-temperature magnetic susceptibility and Mossbauer spectra in zero and various applied fields suggest a complex combination of slow paramagnetic relaxation and weak magnetic order in the range 10-1 K.