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Low‐cost molecular emitters that merge circularly polarized luminescence (CPL) and thermally activated delayed fluorescence (TADF) properties are attractive for many high‐tech applications. However, the design of such emitters remains a difficult task. To address this challenge, here, we propose a simple and efficient strategy, demonstrated by the design of pseudochiral‐at‐metal complexes [Cu(L*)DPEPhos]PF6 bearing a (+)/(−)‐menthol‐derived 1,10‐phenanthroline ligand (L*). These complexes exhibit a yellow CP‐TADF with a record‐high quantum yield (close to 100 %) and high dissymmetry factor (|glum|~1×10−2). Remarkably, the above compounds also show a negative thermal‐quenching (NTQ) of luminescence in the 300–77 K range. Exploiting the designed Cu(I) emitters, we fabricated efficient CP‐TADF OLEDs displaying mirror‐imaged CPL bands with high |gEL| factors of 1.5×10−2 and the maximum EQE of 6.15 %. Equally important, using the (+)‐[Cu(L*)DPEPhos]PF6 complex, we have discovered that an external magnetic field noticeably suppresses CP‐TADF of Cu(I) emitters. These findings are an important contribution to the CPL phenomenon and provide access to highly efficient, low‐cost and robust CP‐TADF emitters. [ABSTRACT FROM AUTHOR]

[Display omitted] The interaction of tris(6-methyl-2-pyridyl)phosphine oxide (L) with equimolar amounts of [Cu(MeCN) 4 ]PF 6 or AgClO 4 in acetonitrile produces scorpionate-like complexes [M(L)(MeCN)]X (M = Cu and Ag; X = PF 6 - and ClO 4 -). At ambient temperature, these compounds exhibit orange (λ max = 608 nm) or turquoise (λ max = 490 nm) photo-luminescence with a quantum yield up to 16% and lifetimes of microsecond order. [ABSTRACT FROM AUTHOR]

New fluorinated dibenzo-1,2,5,6-tetrathiocines 1 and 2 were synthesized by a novel condensation of 1,2-disulfenyl chlorides under the influence of elemental Cu, and structurally defined in the solid state, solution, and gas phase by single-crystal XRD, variable-temperature 19F NMR and NOESY, and DFT calculations. Crystalline 1 and 2 exhibited the C2h chair and C2 twist molecular conformations, respectively. Unlike 1 displayed only C⋯S shortened intermolecular contacts, crystal structure of 2 featured F⋯π, F⋯F, F⋯S and S⋯S contacts. In toluene solutions at 296 K, both twist and chair conformers were observed in the ∼1 : 1 and ∼7 : 1 ratios for 1 and 2, respectively. For 1, the twist ↔ chair conformer interconversion was practically temperature-independent, and for 2 revealed ΔH ∼3.5 kJ mol−1 and ΔS ∼4.4 J K−1 mol−1. With DFT, the PESs for twist–chair transformation and twist–twist racemization were analyzed and the TSs exhibiting twist–halfchair and boat conformations, respectively, were found. Several additional stationary points on the PESs, corresponding to hidden intermediates and bifurcation points and featuring twistboat and halfchair conformations were detected. In chloroform solution under sunlight, 1 underwent 1,2,5,6-tetrathiocine → 1,2,3,6-tetrathiocine isomerization whose product was characterized by XRD. [ABSTRACT FROM AUTHOR]

Rare‐earth element‐free materials that exhibit strong room temperature phosphorescence (RTP) and X‐ray scintillation properties are gaining global interest incessantly in the recent years. This work reports a series of easily synthesizable cubane Cu4I4‐triarsenic clusters [Cu4I4(R3As)3L] (L = none or nitrile), that exhibit a strong yellow‐green RTP with quantum efficiencies up to 100% and short decay times (4.4–4.9 µs). The title cluster complexes display X‐ray scintillation properties with a record ultralow detection limit (18.1 nGy s−1) and a perfectly linear dose rate response within a remarkably wide dose rate window (0–640 µGyair s−1). The cluster [Cu4I4(Ph3As)3] is highlighted as an efficient phosphor for UV‐pumped white and yellow LED devices, demonstrating an excellent white spectrum with a CIE index of (0.32,0.33) and bright yellow emission, respectively. These results may stimulate the future efforts in designing highly efficient arsenic‐based RTP materials and enriching the Cu4I4 cluster family. [ABSTRACT FROM AUTHOR]

A series of complexes [Cu2X2(Pic3PO)2] (X = Cl, Br, I) based on tris(pyridin-2-ylmethyl)phosphine oxide (Pic3PO) has been synthesized. At 298 K, these compounds exhibit thermally activated delayed fluorescence (TADF) of 1(M+X)LCT type with λmax varying from 485 to 545 nm, and quantum efficiency up to 54%. In the TADF process, the halide effect appears as the emission intensification and bathochromic shift of λmax in the following order X = I < Br < Cl. Upon X-ray irradiation, the title compounds emit radioluminescence, the emission bands of which have the same shape as those at TADF, thereby meaning a similar radiative excited state. By contrast to TADF, the halide effect in the radioluminescence is reversed: its intensity grows in the order X = Cl < Br < I, since heavier atoms absorb X-rays more efficiently. These findings essentially contribute to our knowledge about the halide effect in the photo- and radioluminescent Cu(I) halide emitters. [ABSTRACT FROM AUTHOR]

We introduce here a new subclass of copper(I) hybrid emitters simultaneously containing [CuxIy]z- anions and Cu+ cations, separated in space by a Janus head ligand. When UV-irradiated at 298 K, these unique "Two-In-One" hybrids exhibit a short-lived green TADF with near-unity quantum yield and a strong solvatochromic effect. Moreover, they manifest a strong radioluminescence upon X-ray irradiation. These findings open up new possibilities for the design of highly performing TADF materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tris(6-methyl-2-pyridyl)phosphine (L) reacts with Cu(I) halides to afford two neutral [Cu 2 Cl 2 L 2 ], [Cu 4 I 4 L 2 ] and two zwitterionic complexes [Cu 4 Hal 4 L 2 (MeCN) 2 ] (Hal = Br and I). • The structure of the obtained complexes is discussed. • The presented complexes emit phosphorescence at ambient temperature. A series of luminescent Cu(I) complexes has been synthesized by the reactions between tris(6-methyl-2-pyridyl)phosphine (L) and Cu(I) halides. The reaction of L with CuCl in CH 2 Cl 2 forms a binuclear complex [Cu 2 Cl 2 L 2 ], while CuI under the same conditions unexpectedly affords the tetranuclear neutral [Cu 4 I 4 L 2 ] complex. At the same time, the interaction of CuBr or CuI with L in MeCN medium unexpectedly gives rare co-called «All-in-One» complexes [Cu 4 Hal 4 L 2 (MeCN) 2 ] (Hal = Br and I). At ambient temperature, the above compounds display a solid-state luminescence (λ max = 535–565 nm) with emission lifetimes of 1.8–6.9 μs, and the quantum efficiency of up to 80 %. [ABSTRACT FROM AUTHOR]

[Display omitted] A new cubane cluster [Cu 4 I 4 (AsAn 3) 4 ] was synthesized in 82% yield by the reaction of tris(p -anisyl)arsine (AsAn 3) with CuI. At ambient temperature, this cluster exhibits bright yellow-green phosphorescence (λ max = 546 nm) with the quantum yield of 35% and 4.1 μs decay time. [ABSTRACT FROM AUTHOR]

A series of Ag(I), Au(I), Ag(I)-Au(I) and Cu(I)-Au(I) complexes has been synthesized using tris(6-methyl-2-pyridyl)phosphine as an efficient P , N , N ′, N ″ - bridging ligand. Room temperature phosphorescence has been revealed for the obtained compounds. [Display omitted] Tris(6-methyl-2-pyridyl)phosphine (L) has been highlighted as a promising multidentate ligand for design of original clusters based on group 11 metals. The interaction of this ligand with Au(tht)Cl and Au(tht)Cl-KPF 6 system affords complexes [Au(L)Cl] and [AuL 2 ]PF 6 , in which a linear P–Au–P coordination is realized. Complex [AuL 2 ]PF 6 , upon treatment with AgPF 6 or CuPF 6 , unexpectedly forms penta-nuclear clusters [Au@Ag 4 L 4 ](PF 6) 5 and [Au@Cu 4 L 4 ](PF 6) 5 , respectively, showing Au-centered tetrahedral Ag 4 /Cu 4 kernel supported by four L ligands in P , N , N ′, N ″ - bridging manner. The structurally similar all-silver cluster [Ag@Ag 4 L 4 ](BF 4) 5 has been assembled by the direct reaction of L with AgBF 4. According to X-ray crystallography data and QTAIM study, the synthesized clusters {Au@Ag 4 }, {Au@Cu 4 } and {Ag@Ag 4 } feature the pronounced attractive metallophilic d10-d10 interactions between the central (Au/Ag) and peripherical (Cu, Ag) metal atoms. At ambient temperature, the title complexes exhibit room-temperature phosphorescence at λ max = 501–572 nm with emission lifetimes of microsecond order (τ = 0.86–20 µs) and the quantum yields of up to 23 %. [ABSTRACT FROM AUTHOR]