An energetic metal-organic framework (EMOF) [Ag-2(5-ATZ)(N-3)] (1) was hydrothermally prepared and structurally characterized by single crystal X-ray diffraction analysis. 1 features a compacted three-dimensional framework structure and possesses the highest density (rho = 3.4 g cm(-3)) in the known energetic compounds, in which each 5-ATZ ligand possesses a mu(4)-1,2,3,4 coordination mode and each azide group adopts a rare mu(4)-1,1,1,3 bridging mode. 1 exhibits a considerably high thermal stability, with a thermal decomposition temperature of about 300.0 degrees C, and insensitivity to external stimuli. Remarkably, the kinetic triplets (the apparent activation energy (E-a), the preexponential factor (A) and the mechanism function (f(alpha))) are discussed in detail. In addition, the energetic performance and the catalytic effect of 1 on the thermal decomposition of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) were also examined.