Structural insights into T 2 -cluster-containing chalcogenides with vertex-, edge- and face-sharing connection modes of NaQ 6 ligands: Na 3 ZnM III Q 4 (M III = In, Ga; Q = S, Se)

ligands in the title sulfides are also rarely (only 3%) found. Besides, the optical properties including diffuse-reflection and Raman spectra are systematically characterized. Theoretical calculations based on the first principles theory were also used to analyze their structure-performance relationships.