Based on the experimental and simulation data, we propose the ZIF structural modification mechanism shown in Fig. , including a comparison to the well-known modification of silicate glasses by alkali modifiers. The polymerized ZIF network consists of zinc metal nodes connected by bridging organic linkers (X). Addition of the modifier halide salt consisting of a protoncontaining cation (here, a heterocycle denoted [H-A] + ), which may easily exchange its proton (H + ) together with a halide anion (denoted [B -]), results in a partially depolymerized ZIF network. That is, upon heating, the breaking and reformation of Zn-N coordination bonds lead to changes in the coordination framework. During this process, Zn nodes coordinate to mixed linkers of protonated heterocycles as well as the added halide anions. Continued heating of either the existing liquid or the already-formed glass (below the decomposition temperature) may result in evaporation of the loosely bound heterocycle (denoted as A) as well as the non-bridging X-H species, which leads to re-polymerization of the framework. and physical properties through continuous composition variation. We also believe that the present approach will enable new functionalities (fluorescence, sensing, etc.) of MOF glasses through the incorporation of the added salt directly into the existing framework structure.