Colossal negative thermal expansion in a cucurbit[8]uril-enabled uranyl-organic polythreading framework via thermally induced relaxation

Abstract

It is an ongoing goal to achieve effective regulation of thermal expansion properties of materials. In this work, we proposed a method of incorporating host-guest complexation into the skeleton of...

Classifying and Predicting the Thermal Expansion Properties of Metal–Organic Frameworks: A Data-Driven Approach

“…43 Large magnitudes of PTE and NTE were demonstrated in penta-morphic organometallic martensite (α V > 250 MK −1 ) 44 and uranyl-organic poly threading framework (α V = −962.9 MK −1 ). 45 For MOFs, near-colossal NTE of α V = −97 MK −1 was observed in defect UiO-66(Hf), 26 while large volumetric PTE in MOFs is rarely reported. In this regard, a handful of MOFs in our curated data set (i.e., 10,041 MOFs) demonstrate unrealistic magnitudes of α V (i.e., |α V | > 500 MK −1 ).…”

“…In the literature, the term “colossal” thermal expansion often refers to materials with a large magnitude of α V (i.e., |α V | > 100 MK –1 ) . Large magnitudes of PTE and NTE were demonstrated in penta-morphic organometallic martensite (α V > 250 MK –1 ) and uranyl-organic poly threading framework (α V = −962.9 MK –1 ) . For MOFs, near-colossal NTE of α V = −97 MK –1 was observed in defect UiO-66­(Hf), while large volumetric PTE in MOFs is rarely reported.…”

Side-Chain Engineering for Modulating the Mechanical and Thermosalient Behavior of Elastic Crystals of Triple-Helix Coordination Polymers

“…Stimuli-responsive crystalline coordination polymers (CPs) that respond to environmental changes in temperature, − pressure, , light, − and guest molecules , show promising applications in a wide range of fields. − Besides responsiveness in the form of changes in physicochemical properties at the microscopic level such as phase transitions, discoloration, luminescence, , etc., emergent research activities have contributed to the understanding of the macroscopic mechanical response of crystalline CP materials under stimuli such as heat, pressure, and light. ,,,− Among such a class of mechanically responsive CPs, those with multiple mechanical responsiveness that can mechanically respond to two or more kinds of external signals are more desirable. ,, Despite the emergence of mechanically responsive CP materials, there are still significant challenges in tailoring such a kind of material, and a comprehensive understanding of structure–activity relationships and structural features that influence the mechanical responsiveness will be beneficial for enabling custom synthesis on demand in future. − , …”