Luminescent Thermochromism in a Gold(I)–Copper(I) Phosphine–Pyridine Complex

Abstract

The AuI complex [Au(Ph2PCH2py)2]BF4 (1) was prepared by mixing (tetrahydrothiophene)gold(I) chloride with 2‐[(diphenylphosphino)methyl]pyridine (Ph2PCH2py) in dichloromethane. The addition of [Cu(NCCH3)4]BF4 to 1 produced green‐luminescent [AuCu(Ph2PCH2py)2(NCCH3)2](BF4)2 (2). When crystals of 2 were exposed to air, two acetonitrile molecules were lost to form crystals of yellow‐luminescent [AuCu(Ph2PCH2py)2](BF4)2 (3). This simple solvent loss perturbs the environment around the CuI center, and the Au···Cu distance shortens from 3.3 to 2.8 Å. Crystallization of 2 or 3 from dichloromethane produced the two‐coordinate CuI–solvate complex, [AuCu(Ph2PCH2py)2](BF4)2·CH2Cl2 (3·CH2Cl2). Compound 3 exhibits temperature‐dependent emissions from 77 to 298 K (543 nm), 298 to 343 K (551 nm), and above 343 K (505 nm) that is reversed upon return to room temperature. The low‐temperature emission is typical of complexes with luminescent rigidochromic properties. However, based on differential scanning calorimetry, a phase change is responsible for the high‐temperature emission of 3.

Photostable Voltage-Sensitive Dyes Based on Simple, Solvatofluorochromic, Asymmetric Thiazolothiazoles

“…It was observed that the wavelength of emission shows a strong linear correlation with the solution temperature while inside the temperature range in which MeTHF is liquid. Additionally, the TTz/MeTHF solution showed relatively high temperature sensitivity (−0.21 nm °C –1 ), thus making it suitable for temperature-sensing applications. − …”

Organophosphorus Compounds in Organic Electronics

“…Dinuclear Au–Cu phosphine complex 79 (Figure ) shows thermochromic luminescence with three distinct colors ( λ em =543 nm/77–298 K, λ em =551 nm/298–343 K, λ em =505 nm/>343 K) and a solvochromic effect towards CH 3 CN ( λ em =536 nm) in the crystalline state …”

Thermo-responsive light-emitting metal complexes and related materials

“…[1][2][3][4] In particular, thermo-responsive functional materials with specific luminescence changes have attracted wide attention due to their potential applications in temperature sensing, [5][6][7][8][9][10][11][12] biological imaging, [13][14][15][16][17][18][19][20] optoelectronic devices, [21][22][23][24][25] and information processing. [26][27][28] To date, tremendous progress has been made in the development of thermo-responsive light-emitting materials, including various organic dyes and polymers, [29][30][31][32][33][34][35][36][37] metal complexes, [38][39][40][41][42][43][44] metal clusters and metal-organic frameworks (MOFs), [45][46][47][48]…”