ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Tetra- and hexanuclear copper(I) iminothiolate complexes: synthesis, structures, and solid-state thermochromic dual emission in visible and near-infrared regions

Yoshiki Ozawa, Marino Mori, Hidetoshi Kiyooka, Yuumi Sugata, Toshikazu Ono, and Masaaki Abe

Graduate School of Material Science, University of Hyogo, Hyogo, Japan

E-mail: ozawa@sci.u-hyogo.ac.jp

Received: 13 February 2020  Accepted: 13 June 2020

Abstract:

Two new photoluminescent multinuclear Cu(I) cluster complexes supported by monoanionic bidentate ligand N-methylbenzimidazolethiolate (Me-bimt^–), [Cu_n(Me-bimt)_n] with n = 4 (1) and 6 (2), have been synthesized and structurally characterized by single-crystal X-ray diffraction analysis. For 1 and 2, the Cu(I) ions and the Me-bimt^– ligands construct a cubane-type {Cu₄S₄} and a hexagonal-prism {Cu₆S₆} frameworks, respectively. In the crystalline state, complexes 1 and 2 exhibit green (λ_em = 500 nm) and near-infrared (λ_em = 876 nm) emission, respectively, under UV irradiation (λ_ex = 365 nm) at room temperature. Both crystals reveal temperature-dependent dual emission below 200 K: complex 1 emits in the visible wavelength region (λ_em = 493 and 542 nm) and complex 2 in the visible to near-infrared wavelength region (λ_em = 752 and 973 nm) which are attributed to multiple photoexcited states at the cluster frameworks with distinct metal nuclearity.

Keywords: Copper(I); Cluster compounds; Crystal structure; Thermochromic dual emission; Near-infrared emission

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-020-01251-w

Chemical Papers 74 (11) 3717–3725 (2020)