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The new series of copper(I) coordination polymers [Cu(N-N)(μ-PTA)] n [PF 6 ] n {N-N = dmbpy ( 1 ), bpy ( 2 ), ncup ( 3 ), and phen ( 4 )} were generated by straightforward reaction in solution or through a mechanochemical route, of [Cu(MeCN) 4 ][PF 6 ] with 1,3,5-triaza-7-phosphaadamantane (PTA) and the corresponding polypyridines, namely, 5,5'-dimethyl-2,2'-bipyridine (dmbpy), 2,2'-bipyridine (bpy), 2,9-dimethyl-1,10-phenanthroline (ncup), and 1,10-phenanthroline (phen). The compounds were obtained as air-stable solids and fully characterized by IR, NMR spectroscopy, and elemental analyses. The molecular structures were confirmed by single-crystal X-ray diffraction analysis (for 1 , 2 , and 4 ), revealing infinite one-dimensional (1D) linear chains driven by μ-PTA N,P -linkers. All tested Cu(I) polymeric compounds show emission at room temperature, which was attributed to thermally activated delayed fluorescence (TADF). Evidence of the involvement of the excited singlet state in the emission process is presented. Comparing the photophysical properties of 1 and 2 as well as 3 and 4 , of which 1 and 3 have a stiffened structure, by introducing a methyl group to one of the ligands, we demonstrate how TADF properties depend on molecular rigidity. It is shown that stiffening of the structure reduces the flattening distortion around the Cu(I) center in the 3 MLCT state. As a result, the Δ E (S 1 -T 1 ) energy gap becomes smaller and the fluorescence quantum yield increases without significantly extending the emission lifetime. In particular, the Δ E (S 1 -T 1 ) values for complexes 1 and 3 are among the shortest reported in the scientific literature, 253 and 337 cm -1 , and the TADF lifetimes are τ(300 K) = 5.7 and 4.2 μs, respectively. The fluorescence quantum yields for these complexes are measured to be Φ PL (300 K) = 70 and 80%.

A macrocyclic motif composed of carbazole and pyridine subunits linked by a carbonyl bridge (C═O) forms a skeleton with a peripheral reactivity that leads to a pinacol-like coupling activated by BBr 3 , eventually entrapping a substantially elongated C-C bond. Slightly modified conditions lead to the efficient transformation of the C═O unit to a CH 2 linker that, after exposure to air, gives a dimeric molecule with multiple bonds between two macrocyclic units, as documented in spectroscopy and X-ray analysis.

The first discrete hexanuclear metal clusters with cores adopting the M6(μ-O)12 cubo-octahedral topology have been synthesized in the course of a simple one-pot reaction. We present a new class of rhenium clusters which are the first hexanuclear rhenium complexes with 12 bridging ligands and the first clusters with octahedrally arranged Re atoms bridged only by O atoms forming a unique cube-like Re6(μ-O)12 unit. Our synthetic strategy demonstrates a new approach to the syntheses of polynuclear rhenium complexes under mild conditions. We discovered that the [Re6(μ-O)12(3-Mepy)6]BPh4 cluster compound has the ability to undergo reversible or/and quasireversible redox reactions without changing spatial structure and overall geometry. Subsequently, a reduction reaction of [Re6(μ-O)12(3-Mepy)6]BPh4 was performed successfully and almost quantitatively resulting in the formation of the molecular [Re6(μ-O)12(3-Mepy)6] complex.

In a 1D network of (1)(∞){[Fe(CH(3)CN)(4)(pyrazine)](ClO(4))(2)}, the presence of four neutral nitrile molecules besides the pyrazine donors in the first coordination sphere of iron(II) allows one to achieve a ligand field strength appropriate for the "spin-crossover" occurrence.