Preparation and Solid-State Structural, Electronic, and Magnetic-Properties of the 5-Cyano-1,3-Benzene-Bridged Bis(1,2,3,5-Dithiadiazolyl) and Bis(1,2,3,5-Diselenadiazolyl) [5-Cn-1,3-C6h3(cn2e2)2] (E = S, Se)

by Cordes, A. Wallace; Haddon, Robert C.; Hicks, Robin G.; Kennepohl, Dietmar K.; Oakley, Richard T.; Palstra, Thomas T. M.; Schneemeyer, Lynn F.; Scott, Syrona Renae Horton; Waszczak, Joseph V.

The preparation and solid-state characterization of the bifunctional radicals [4,4'-(5-cyanobenzene)-1,3-bis(1,2,3,5-dithiadiazolyl)] and [4,4'-(5-cyanobenzene)-1,3-bis(1,2,3,5-diselenadiazolyl)] [5-CN-1,3-CrH3(CN2E2)2] (E = S, Se) are described. The crystals of the two title compounds are isomorphous and belong to the monoclinic space group P2(1)/c, with (for E = S) a = 7.00(2), b = 30.050(6), c = 10.713(8) angstrom, beta = 104.80(10)-degrees, V = 2179(6) angstrom3, z = 8 and (for E = Se) a = 7.124(4), b = 30.50(2), c = 10.874(2) angstrom, beta = 105.46(3)-degrees, V = 2277(2) angstrom3, Z = 8. The crystal structures consist of stacks of diradicals running parallel to x; radical dimerization up and down the stack generates a zigzag arrangement, as seen in the related 1,3-phenylene structures. Along the stacking axis the mean intradimer E-E contacts are 3.12 (E = S) and 3.23 angstrom (E = Se), while the mean interdimer E- - -E distances are 3.89 (E = S) and 3.91 angstrom (E = Se). Magnetic and conductivity data are presented and discussed in light of extended Huckel band structure calculations.

Journal
Chemistry of Materials
Volume
5
Issue
6
Year
1993
Start Page
820
ISBN/ISSN
1520-5002; 0897-4756
DOI
10.1021/cm00030a017