Solid-State Luminescence of Au-Cu-Alkynyl Complexes Induced by Metallophilicity-Driven Aggregation

Research output: Contribution to journalArticleScientificpeer-review

Researchers

  • Igor O. Koshevoy
  • Yuh-Chia Chang
  • Antti Karttunen

  • Julia R. Shakirova
  • Janne Janis
  • Matti Haukka
  • Tapani Pakkanen
  • Pi-Tai Chou

Research units

  • University of Eastern Finland
  • National Taiwan University
  • University of Jyväskylä
  • St. Petersburg State University

Abstract

A new series of homoleptic alkynyl complexes, [{Au2Cu2(C2R)4}n] (R=C3H7O (1), C6H11O (2), C9H19O (3), C13H11O (4)), were obtained from Au(SC4H8)Cl, Cu(NCMe)4PF6, and the corresponding alkyne in the presence of a base (NEt3). Complexes 14 aggregate upon crystallization into polymeric chains through extensive metallophilic interactions. The cluster that contains fluorenolyl functionalities, C13H9O (5), crystallizes in its molecular form as a disolvate, [Au2Cu2(C2C13H9O)4]2THF. The substitution of weakly bound THF molecules with pyridine molecules leads to the complex [Au2Cu2(C2C13H9O)4]2py (6), thus giving two polymorphs in the solid state. Such structural diversity is established through metal-chain and hydrogen-bond formation, which depends on the stereochemical characteristics of the organic ligands. More interestingly, this solid-state structural arrangement affords good emission properties, such as intensity and spectroscopic profile, which are otherwise very weakly emissive in solution. Metallophilic aggregation of the {Au2Cu2} cluster units, as observed in the crystals, results in dramatic enhancement of the room-temperature phosphorescence, thereby reaching a maximum quantum efficiency of 95% (4). A theoretical approach further indicates a synergistic effect of the array of the metal chain upon aggregation, which greatly enhances the spin-orbit coupling and, hence, the phosphorescence, thereby opening up a new direction in the field of aggregate-enhanced emission.

Details

Original languageEnglish
Pages (from-to)5104-5112
Number of pages9
JournalCHEMISTRY: A EUROPEAN JOURNAL
Volume19
Issue number16
Publication statusPublished - Apr 2013
MoE publication typeA1 Journal article-refereed

    Research areas

  • aggregation, copper, gold, luminescence, polymers, LIGHT-EMITTING-DIODES, CYCLOMETALATED ALKYNYLGOLD(III) COMPLEXES, APPROXIMATE COULOMB POTENTIALS, DENSITY-FUNCTIONAL METHODS, TRIPLET EXCITED-STATES, AUXILIARY BASIS-SETS, INDUCED EMISSION, I COMPLEXES, AUROPHILIC INTERACTIONS, COPPER(I) COMPLEXES

ID: 6676425