| Summary: | Two silver nitrate complexes with bisphosphines were obtained and characterized: [Ag(dcypm)]<sub>2</sub>(NO<sub>3</sub>)<sub>2</sub> (<b>1</b>; dcypm = bis(dicyclohexylphosphino)methane) and [Ag(dppm)]<sub>2</sub>(Me<sub>2</sub>Pz<sup>H</sup>)<sub>n</sub>(NO<sub>3</sub>)<sub>2</sub> (n = 1, <b>2a</b>; n = 2, <b>2b</b>; dppm = bis(diphenylphosphino)methane, Me<sub>2</sub>Pz<sup>H</sup> = 3,5-dimethylpyrazole). The steric repulsions of bulky cyclohexyl substituents prevent additional ligand coordination to the silver atoms in <b>1</b>. Compounds obtained feature the bimetallic eight-member cyclic core [AgPCP]<sub>2</sub>. The intramolecular argenthophilic interaction (d(Ag···Ag) = 2.981 Å) was observed in complex <b>1</b>. In contrast, the coordination of pyrazole led to the elongation of Ag···Ag distance to 3.218(1) Å in <b>2a</b> and 3.520 Å in <b>2b</b>. Complexes 1 and 2a possess phosphorescence both in the solution and solid state. Time-dependent density-functional theory (TD-DFT) calculations demonstrate the origin of their different emission profile. In the case of <b>1</b>, upon excitation, the electron leaves the Ag–P bonding orbital and locates on the intramolecular Ag···Ag bond (metal-centered character). Complex <b>2a</b> at room temperature exhibits a phosphorescence originating from the <sup>3</sup>(M + L<sup>P+N</sup>)L<sup>Ph</sup>CT state. At 77 K, the photoluminescence spectrum of complex <b>2a</b> shows two bands of two different characters: <sup>3</sup>(M + L<sup>P+N</sup>)L<sup>Ph</sup>CT and <sup>3</sup>LC<sup>Ph</sup> transitions. The contribution of Ag atoms to the excited state in both complexes <b>2a</b> and <b>2b</b> decreased relative to <b>1</b> in agreement with the structural changes caused by pyrazole coordination.
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