Jian-Gang Xu

Grinding size-dependent mechanoresponsive luminescent Cd(II) coordination polymer

In this work, we report a new mechanoresponsive luminescent Cd(ii) coordination polymer that exhibits a sensitivity to mechanical stimulation. The luminescence colour changed gradually from weak yellowish-green to bright cyan in response to different grinding sizes, thereby showing interesting mechanochromic properties, namely a grinding-enhanced luminescence and good crystalline maintenance ability.

A 3D metal–organic framework built from vanadate clusters and diamond chains showing weak ferromagnetic single-chain-magnet like behavior

Magnetically weakly coupled diamond chains in the 3D metal–organic framework are well separated by diamagnetic [V4O12]4− cluster units and semi-rigid ligands, and exhibit not only weak ferromagnetic interactions with frustrated spin canting but also single-chain magnets with slow magnetic relaxation below 3.4 K.

Nitrogen-Rich Tetranuclear Metal Complex as a New Structural Motif for Energetic Materials

For designing energetic materials (EMs), the most challenging issue is to achieve a balance between energetic performance and reliable stability. In this work, we employed an efficient and convenient method to synthesize a new class of EMs: nitrogen-rich tetranuclear metal complexes [M(Hdtim)(H2O)2]4 (M = Zn 1, Mn 2; H3dtim = 1H-imidazol-4,5-tetrazole) with the N content of >46%. The structural analyses illustrate that isomorphous compounds 1 and 2 feature isolated hollow ellipsoid tetranuclear units, which are linked by both π–π interactions and hydrogen-bonding interactions to give a 3D supramolecular architecture. Compounds 1 and 2 exhibit prominent energetic characteristics: excellent detonation performances and reliable thermal, impact, and friction stabilities. Being nitrogen-rich tetrazolate compounds, the enthalpies of combustion of 1 (−11.570 kJ g–1) and 2 (−12.186 kJ g–1) are higher than those of classical EMs, RDX and HMX, and they possess high positive heats of formation. Sensitivity tests demonstrate that 1 and 2 are insensitive to external mechanical action. Excellent energetic performances and low sensitivities promote 1 and 2 to serve as a new class of promising EMs with a desirable level of safety.

An enhanced extended hook method to realize tetranuclear metal clusters embedded in energetic metal–organic framework channels

Rare tetranuclear Zn clusters were successfully embedded into 3D energetic metal–organic framework channels by an enhanced extended hook method. The obtained metal–organic framework exhibits not only high enthalpy of combustion and low sensitivity but also strong green fluorescence.

A highly stable and tightly packed 3D energetic coordination polymer assembled from nitrogen-rich tetrazole derivatives

An energetic coordination polymer ([Cd(BTA)(H2O)]n1 (H2BTA = N,N-bis(1(2)H-tetrazol-5-yl)-amine)) was solvothermally synthesized and structurally characterized. The structural analyses illustrate that compound 1 exhibits a nonporous, tightly packed 3D PtS framework. Compared with the porous 3D metal–organic framework CoBTA (CoBTA = [Co9(bta)10(Hbta)2(H2O)10]n), 1 displays higher density, better water resistance and thermal stability, and lower sensitivities. The enthalpy of formation of 1 is 0.7519 kJ g−1, which is higher than that of the traditional explosive 2,4,6-trinitrotoluene (TNT, −0.2952 kJ g−1). The detonation velocity (D) and detonation pressure (P) of 1 were calculated to be 6.283 km s−1 and 21.64 GPa, respectively. Sensitivity tests reveal that 1 is insensitive to external stimuli. Based on the evaluation of energetic performance, 1 can act as an energetic candidate material with an approved level of safety.