A 2,3‐Connected Tellurium Net and the Cs 3 Te 22 Phase

The bonding in the recently reported Cs 3 Te 22 phase, which contains both Te 8 rings and remarkable Te 6 sheets, is studied by approximate molecular orbital theory. Our focus is on the geometric and electronic features of the unique 2,3‐connected Te net found as a substructure in this phase. The calculations show that both the linear and T‐shaped Te geometries in the 2,3‐connected Te net of Cs 3 Te 22 are determined by their particular electron count. Both types of tellurium atoms are hypervalent; we make connections to other well known hypervalent molecules, such as XeF 2 , I 3 − , and BrF 3 . Several possible variations and distortions of this net are discussed, all of which are found to be less stable. The discrete crown‐shaped Te 8 units that appear in the phase show normal covalent bonding and should occur in smaller molecular entities, too. According to our computations, Cs 3 Te 22 should be metallic. Two structurally related phases, CsTe 7 and Cs 2 Te 15 , are suggested.