The metal-organic framework Zn5Cl4(btdd)3 (ZnCl-MFU-4l, previously referred to as MFU-4l) consists of pentanuclear zinc clusters connected by linear bisbenzotriazolate linkers (btdd 2-) to form a highly porous cubic network structure (Figure ). Each pentanuclear cluster has one octahedral zinc site at the center and four pseudo-tetrahedral zinc sites that are capped by terminal chloride anions and exposed to the pore of the framework. A variety of post-synthetic metal exchanges and anion exchanges at the peripheral sites have been reported for ZnCl-MFU-4l and related frameworks, allowing for control over gas adsorption and catalysis properties. Nonetheless, to the best of our knowledge, no studies have aimed to change the identity of the central metal site to alter properties of the peripheral metal sites. This is possibly because the central metal site is inaccessible within the cluster, prohibiting post-synthetic metal-exchange in MFU-4l. The inaccessibility of the central metal for post-synthetic metal-exchange may lead to the incorrect assumption that the central metal does not significantly impact the surface properties of these materials.