Novel Double-Stranded Chains vs Two-Layer Interwoven Sheets. Subtle Coligand Effects and Related Properties for [Co(Py2S)(2)X-2](n) (Py2S = 4,4'-Dipyridyl Sulfide; X = NCS, CI).A study of striking structural differences in the magic angle of Py2S and coligand effects has been carried out. [Co(Py2S)(2)Cl-2](n) is the first integral two-layer interwoven sheet without any counterion or solvate whereas [Co(Py2S)(2)(NCS)(2)](n) affords a double-stranded linear infinite structure. Thermal analyses of the complexes over the temperature range 25-430 degrees C show the significant thermal behaviors associated with the structure.