Self assembly of sandwich-layered 2D silver(I) coordination polymers stabilized by argentophilic interactions: Synthesis, crystal structures and ab initio intramolecular energetics

Evolution of Oxidizing Inorganic Metal Salts: Ultrafast Laser Initiation Materials Based on Energetic Cationic Coordination Polymers

An effective and novel design strategy for ultrafast laser-initiating materials has been established on the basis of coordination chemistry for the first time in the present work. In view of the positive effect of Ag ion and perchlorate on laser sensitivity, silver perchlorate as a representative of oxidizing inorganic metal salts was used to construct energetic cationic coordination polymers (ECCPs), which solved the inconvenient situation caused by the difficulty in applying these salts directly in energetic materials because of the unavoidable hygroscopicity and the inhomogeneity of physical mixtures of oxidants and reductants. With the nonenergetic nitrogen-rich ligand 3-amino-1H-1,2,4-triazole-5-carbohydrazide (ATCA), one new laser-sensitive Ag(I)-based ECCP [Ag(ATCA)ClO₄]_n (1) was successfully synthesized with a compact helical structure proved by X-ray single-diffraction crystal data. The physicochemical property evaluation revealed that this Ag-ECCP was not only completely devoid of the undesirable properties of the silver perchlorate and displayed excellent tolerance to moisture and noncorrosive properties to metal shells, but was also endowed with good thermal stability and excellent safety for mechanical stimulation. Moreover, theoretical calculations based on the standard molar enthalpy of formation and the lead plate explosive test as the actual damage experiment have proved that the compound has a superior detonation performance (up to 6800 m s^-1 and 0.511 kcal g^-1) compared to the traditional primary explosives. More importantly, the laser-initiation-experiment-based femtosecond laser-testing system and high-speed photography demonstrated that this ECCP was an energetic material with great potential for application in the safety detonator as an ultrafast photosensitive initiating material for laser direct initiation, whose initiation delay time is as low as 73 ms using only 200 mJ initiation energy.

Silver(I) coordination polymers assembled from flexible cyclotriphosphazene ligand: structures, topologies and investigation of the counteranion effects

The reactions of a flexible ligand hexakis(3-pyridyloxy)cyclotriphosphazene (HPCP) with a variety of silver(I) salts (AgX;X= NO3−, PF6−, ClO4−, CH3PhSO3−, BF4−and CF3SO3−) afforded six silver(I) coordination polymers, namely {[Ag2(HPCP)]·(NO3)2·H2O}n(1), {[Ag2(HPCP)(CH3CN)]·(PF6)2}n(2), {[Ag2(HPCP)(CH3CN)]·(ClO4)2}n(3), [Ag3(HPCP)(CH3PhSO3)3]n(4), [Ag2(HPCP)(CH3CN)(BF4)2]n(5) and {[Ag(HPCP)]·(CF3SO3)}n(6). All of the isolated crystalline compounds were structurally determined by X-ray crystallography. Changing the counteranions in the reactions, which were conducted under similar conditions ofM/Lratio (1:1), temperature and solvent, resulted in structures with different types of topologies. In complexes (1)–(6), the ligand HPCP shows different coordination modes with AgIions giving two-dimensional layered structures and three-dimensional frameworks with different topologies. Complex (1) displays a new three-dimensional framework adopting a (3,3,6)-connected 3-nodal net with point symbol {4.62}2{42.610.83}. Complexes (2) and (3) are isomorphous and have a two-dimensional layered structure showing the same 3,6L60 topology with point symbol {4.26}2{48.66.8}. Complex (4) is a two-dimensional structure incorporating short Ag...Ag argentophilic interactions and has a uninodal 4-connectedsql/Shubnikov tetragonal plane net with {44.62} topology. Complex (5) exhibits a novel three-dimensional framework and more suprisingly contains twofold interpenetrated honeycomb-like networks, in which the single net has a trinodal (2,3,5)-connected 3-nodal net with point symbol {63.86.12}{63}{8}. Complex (6) crystallizes in a trigonal crystal system with the space group R\bar 3 and possesses a three-dimensional polymeric structure showing a binodal (4,6)-connectedfshnet with the point symbol (43.63)2.(46.66.83). The effect of the counteranions on the formation of coordination polymers is discussed in this study.