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 the effective regulation of the thermal expansion properties of materials. In this work, we propose a method for incorporating host-guest complexation into a framework structure and construct a flexible cucurbit[8]uril uranyl-organic polythreading framework, U₃(bcbpy)₃(CB8). U₃(bcbpy)₃(CB8) can undergo huge negative thermal expansion (NTE) and has a large volumetric coefficient of -962.9 × 10^-6 K^-1 within the temperature range of 260 K to 300 K. Crystallographic snapshots of the polythreading framework at various temperatures reveal that, different from the intrinsic transverse vibrations of the subunits of metal-organic frameworks (MOFs) that experience NTE via a well-known hinging mo

SUBMITTER: Jin QY 

PROVIDER: S-EPMC10266465 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature