Two Novel One-Dimensional α-Keggin-Based Coordination Polymers with Argentophilic {Ag3}3+/{Ag4}4+ Clusters

Two novel alpha-Keggin anion-based coordination polymers with argentophilic {Ag-3}(3+)/{Ag-4}(4+) clusters, [{Ag-3(bpy)(4)}-{PMo12O40}]center dot 2H(2)O (1), [{Ag(bpy)}(2){Ag-4(bpy)(6)}{PMoIIVO40}][{Ag(bpy)}(2){PMoIIVO40}] (2), have been hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. The crystal data for these are the following: C40H36Ag3Mo12N8O42P (1), triclinic P (1) over bar, a = 10.5245(19) angstrom, b = 12.058(2) angstrom, c = 13.530(2) angstrom, alpha = 87.015(2)degrees, beta = 72.146(2)degrees, gamma = 86.563(2)degrees, Z = 1; C100H80Ag8Mo22N20O80P2V2 (2), triclinic P (1) over bar, a = 13.3603(15) angstrom, b = 16.3035(18) angstrom, c = 16.7523(19) angstrom, alpha = 89.896(2)degrees, beta = 84.000(2)degrees, gamma = 88.066(2)degrees, Z = 1. Polymer 1 consists of an infinite zigzag one-dimensional (1D) chain constructed from [Ag-3(bpy)(4)](3+) clusters and [PMo12O40](3-) anions. Polymer 2 consists of isolated bisupporting [{Ag(bpy)}(2){PMoIIVO40}](2-) anions and infinite 1D cationic chains [{Ag(bpy)}(2){Ag-4(bpy)(6)}{PMoIIVO40}](2+) constructed from [{Ag(bpy)}(2){PMoIIVO40}](2-) anions bridged via {Ag-4(bpy)(6)}(4+) clusters. Argentophilic {Ag-3}(3+) and {Ag-4}(4+) interactions exist in polymers 1 and 2. Ag center dot center dot center dot Ag interactions were proven using density functional theory, and the luminescent properties were investigated in polymers 1 and 2. The electrochemical behavior of the polymers modified carbon paste electrode (1-CPE, 2-CPE) and their electrocatalytic reductions of nitrite were investigated. Both 1-CPE and 2-CPE show good electrocatalytic activity toward the reduction of the nitrite and remarkable stability that can be ascribed to their insolubility.