Semiconducting Lead−Sulfur−Organic Network Solids

The reactions of Pb(OAc)2 with 1,2,4,5-benzenetetrathiol, 1,4-benzenedithiol, and benzenehexathiol in ethylenediamine yield bright yellow [Pb2(S2C6H2S2)(en)] n , orange-red [Pb3(SC6H4S)3(en)2] n , and brown [Pb3C6S6] n , respectively. The structures of [Pb2(S2C6H2S2)(en)] n and [Pb3C6S6] n were solved by synchrotron X-ray powder diffraction, while the structure of [Pb3(SC6H4S)3(en)2] n was solved by single-crystal X-ray diffraction. The bonding in [Pb2(S2C6H2S2)(en)] n indicates the presence of “molecular” units, while in [Pb3C6S6] n , the bonding most resembles that in an inorganic solid such as PbS. The differences in bonding are reflected in the optical and electrical properties of the materials; [Pb3C6S6] n is a semiconductor.