Negative Linear Compressibility Response to Pressure in Multitype Wine-Rack Metal–Organic Frameworks

The multifunctional mechanical property, negative linear compressibility (NLC), could arise in the crystals consisting of wine-racklike networks. A typical wine-racklike unit usually expands along its longer diagonal and shrinks along its shorter diagonal under compression. The previous researches concentrated just on materials with homogeneous wine-rack motif in their structures. Herein, we report a novel NLC behavior with a large value of −47.3 TPa–1 in metal-organic frameworks, MCF-34, whose crystal structure consists of four kinds of orientations of wine-rack units shaped in two types. The NLC behavior of MCF-34 arises in a vector direction composed of all the longer diagonals from the four different oriented wine-rack units. This discovery helps us comprehend the mechanical response of a single material with multitype wine-rack units under high pressure. This work is of great guiding significance to design and synthesize customized materials with excellent mechanical properties.