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Uniaxial Negative Thermal Expansion and Mechanical Properties of a Zinc-Formate Framework.

ABSTRACT: The thermal expansion behavior of a metal-formate framework, Zn(HCOO)?·2(H?O) (1), has been systematically studied via variable temperature single-crystal X-ray diffraction. Our results demonstrate that this formate exhibits significant negative thermal expansion (NTE, -26(2) MK^-1) along its c-axis. Detailed structural analyses reveal that the large NTE response is attributed to the 'hinge-strut' like framework motion. In addition, the fundamental mechanical properties of framework 1 have been explored via nanoindentation experiments. The measured elastic modulus and hardness properties on the (00-2)/(100)/(110) facets are 35.5/35.0/27.1 and 2.04/1.83/0.47 GPa, respectively. The stiffness and hardness anisotropy can be correlated well with the underlying framework structure, like its thermoelastic behavior.

SUBMITTER: Gao H

PROVIDER: S-EPMC5459151 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Uniaxial Negative Thermal Expansion and Mechanical Properties of a Zinc-Formate Framework.

Gao Hongqiang H Wei Wenjuan W Li Yizhang Y Wu Rong R Feng Guoqiang G Li Wei W

Materials (Basel, Switzerland) 20170210 2

The thermal expansion behavior of a metal-formate framework, Zn(HCOO)₂·2(H₂O) (1), has been systematically studied via variable temperature single-crystal X-ray diffraction. Our results demonstrate that this formate exhibits significant negative thermal expansion (NTE, -26(2) MK-1) along its c-axis. Detailed structural analyses reveal that the large NTE response is attributed to the 'hinge-strut' like framework motion. In addition, the fundamental mechanical properties o ...[more]

PMID: 28772512

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