Understanding the Origin of Phosphorescence in Bismoles: A Synthetic and Computational Study

Abstract

A series of bismuth heterocycles, termed bismoles, were synthesized via the efficient metallacycle transfer (Bi/Zr exchange) involving readily accessible zirconacycles. The luminescence properties of three structurally distinct bismoles were explored in detail via time-integrated and time-resolved photoluminescence spectroscopy using ultrafast laser excitation. Moreover, time-dependent density functional theory computations were used to interpret the nature of fluorescence versus phosphorescence in these bismuth-containing heterocycles and to guide the future preparation of luminescent materials containing heavy inorganic elements. Specifically, orbital character at bismuth within excited states is an important factor for achieving enhanced spin-orbit coupling and to promote phosphorescence. The low aromaticity of the bismole rings was demonstrated by formation of a CuCl π-complex, and the nature of the alkene-CuCl interaction was probed by real-space bonding indicators derived from Atoms-In-Molecules, the Electron Localizability Indicator, and the Non-Covalent Interaction index; such tools are of great value in interpreting nonstandard bonding environments within inorganic compounds.

Applications of Heteroatom‐Based Oligomers and Polymers in Optoelectronics

“…Nevertheless, it has already been clearly established that heavier atom derivatives offer specific advantages in comparison with their widely used carbon, sulfur or nitrogen analogues. There are many other heteroatom-scaffolds described in the literature (containing Bi, S, Te, or As..) 92,93,94,95 which could potentially be used for the development of new efficient -conjugated materials for optoelectronic applications. The next challenge is clearly to exploit these novel organic materials for the fabrication of optoelectronic devices.…”

The Dawn of Functional Organoarsenic Chemistry

“…The emission color of dithienoarsole luminophores wasa lso controlled by oxidation (22)o rc oordination to gold(I) chloride…”

“…However, investigations of “arsoles” from the viewpoint of materials science remain to be performed, although some arsole derivatives were synthesized up to the 1960s . If studies on pnictogen‐type heteroles are performed by experimental means, pyrrole, phosphole, stibole, and bismole derivatives are prepared, but their arsenic analogues tend to be excluded. Nevertheless, computational studies have constantly predicted the intrinsic natures of arsoles: frontier orbitals, inversion energies, and aromaticity .…”

“…However,i nvestigations of "arsoles" from the viewpoint of materials science remaint ob ep erformed, although some arsole derivatives were synthesized up to the 1960s. [4][5][6][7][8] If studies on pnictogen-type heteroles are performed by experimental means, pyrrole, [9][10][11][12][13] phosphole, [14][15][16][17] stibole, [18,19] and bismole [20][21][22] derivatives are prepared, but their arsenic analoguest end to be excluded.N evertheless, computational studies have constantly predicted the intrinsic natures of arsoles: frontier orbitals, inversion energies, and aromaticity. [23][24][25][26][27][28][29][30] Ta king into consideration growingi nterest in heavy-element-containing molecules, [31] studies on functional organoarsenic chemistry is attractive thanks to the air-stable trivalent state [3] and possibility of the heavy-atom effect.…”

Peraryl Arsoles: Practical Synthesis, Electronic Structures, and Solid‐State Emission Behaviors

“…[3][4][5][6][7] In 2001, Ta ng et al proposed an aggregation-induced emission (AIE) phenomenon of 1-methyl-1,2,3,4,5-pentaphenylsilole. [4] After this seminal work, AIE luminogens based on peraryl heteroles,f or example, pyrrole, [5] thiophene, [6] phosphole, [7] tellurophene, [8] and bismole, [9] have been reported. [4] After this seminal work, AIE luminogens based on peraryl heteroles,f or example, pyrrole, [5] thiophene, [6] phosphole, [7] tellurophene, [8] and bismole, [9] have been reported.…”