Syntheses, Structures, and Electronic Properties of a New Series of Tellurides of the Type [Sequestered Cation]2(Tex) (x = 1–4)

Abstract

AbstractThe list of “classical” tellurides with organic cations was expanded by the synthesis of single‐crystalline salts [Li2(en)n](Tex) (en = ethylenediamine) with n = 4, x = 1 (1), n = 4, x = 2 (2), and n = 5, x = 3 (3), [K(18c6)]2(Tex) (18c6 = 1, 4,7, 10, 13, 16‐hexaoxacycloocta‐decane) with x = 2 (4), 4 (5), [K(18c6)]2[K(en)]2(Te2)2 (6), and [K([2.2.2]crypt)]2(Te2) (7) ([2.2.2]crypt = 4, 7,13, 16, 21, 24‐hexaoxa‐1, 10‐diazabicyclo[8.8.8]‐hexacosane). Electronic structure calculations on free molecules and periodic approaches are discussed and compared with experimental UV/Vis spectra, providing a correlation of the bandgaps with the telluride chain length, and a possibility for affecting the gap by according choice of the counterions. Additionally, 125Te NMR chemical shifts of the presented series of en solvated lithium tellurides are presented.