Microwave-Assisted Preparation, Morphological, and Photoacoustic Studies of the Na4SnSe4, K4Sn2Se6, and K4Sn3Se8, Zintl Molecular Sn–Se Oligomers

The Zintl compounds Na4SnSe4, K4Sn2Se6, and K4Sn3Se8 were prepared for the first time using the microwave-assisted solidstate reaction method. The heteroanions of these phases represent oligomeric group of (zero-dimensional) molecular anions: [SnSe4]4-, [Sn2Se6]4-, [Sn3Se8]4-. The compounds were characterized using Powder XRD, SEM-EDS, and their electronic properties were studied using photoacoustic spectroscopy. The microwave method was found to be simple, fast and efficient for the preparation of these Zintl compounds.