New examples of mixed organochalcogene compounds: Synthesis, structural features and spectroscopic data of [PhSe(etu)][PhTeX4] (Ph = phenyl; etu = ethylenethiourea; X = Br, I)

(PhSe)2 reacts with Br2, ethylenethiourea and PhTeBr3, further with I2, ethylenethiourea and PhTeI3, to give [PhSe(etu)][PhTeBr4] (1) (Ph = phenyl; etu = ethylenethiourea) and [PhSe(etu)][PhTeI4] (2) in very good yields. The tellurium centers present a distorted octahedral configuration, achieved through dimerization involving secondary, reciprocal Te···X interactions. In both compounds the anionic dimmers are linked through X···X interactions, attaining a one-dimensional, polymeric assembly along the b axis. Cations and anions are linked through short Se···X contacts. In addition to single crystal X-ray data, multinuclear NMR results for 1 and 2 are also presented and discussed.