Crystal and electronic structure of the new quaternary sulfides TlLnAg2S3 (Ln = Nd, Sm and Gd)

Three new isostructural sulfides were identified, namely TlLnAg2S3 with Ln = Nd, Sm and Gd, adopting a new structure type. These sulfides are yellow/orange semiconductors, containing a three-dimensional network of condensed AgS4 tetrahedra with the lanthanide and thallium atoms filling one-dimensional channels.187