title: Homoconjugation/homoaromaticity in main group inorganic molecules.
abstract: Quantum chemical computations show that three groups of inorganic ions and neutral molecules, whose structures have long been known and characterized, are aromatic due to through-space homoconjugation: (i) I(4)(2+), S(6)N(4)(2+), and S(2)I(4)(2+) dications and the (O(2))(4) cluster with pericyclic transition-state-like (PTS-like) homoaromaticity; (ii) the bishomoaromatic Te(6)(2+) and 1,5-diphosphadithiatetrazocines; and (iii) the spherically homoaromatic Te(6)(4+). The S(2)I(4)(2+) dication has an unusually high S-S bond order (approximately 2.3) and dual PTS-like aromaticity arising from two separate sets of four-center, six-electron (4c-6e) in-plane through-space conjugation. The diamagnetic (O(2))(4) structural unit recently observed in epsilon-phase oxygen solid has quadruple PTS-like aromaticity, each arising from 4c-6e in-plane through-space conjugation within an O(2)-O(2) plane. Finally, we note that the lighter S(6)(4+) and Se(6)(4+) homologues of Te(6)(4+) also are spherically homoaromatic and might be observable in complexes.
authors: State Key Laboratory for Physical Chemistry of Solid Surface and Center for Theoretical Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
authors: Qin
authors: Q
authors: Zhang
authors: Shiping
authors: S
authors: Yue
authors: Xin
authors: X
authors: Lu
authors: Zhongfang
authors: Z
authors: Chen
authors: Rongbin
authors: R
authors: Huang
authors: Lansun
authors: L
authors: Zheng
authors: Paul von Ragué
authors: Pv
authors: Schleyer