Yeung Hamish H-M, Kilmurray Rebecca, Hobday Claire L, McKellar Scott C, Cheetham Anthony K, Allan David R, Moggach Stephen A
Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK.
EaStChem School of Chemistry and Centre for Science at Extreme Conditions, University of Edinburgh, David Brewster Road, Joseph Black Building, Edinburgh EH9 3FJ, UK.
Phys Chem Chem Phys. 2017 Feb 1;19(5):3544-3549. doi: 10.1039/c6cp08690j.
By decoupling the mechanical behaviour of building units for the first time in a wine-rack framework containing two different strut types, we show that lithium l-tartrate exhibits NLC with a maximum value, K = -21 TPa, and an overall NLC capacity, χ = 5.1%, that are comparable to the most exceptional materials to date. Furthermore, the contributions from molecular strut compression and angle opening interplay to give rise to so-called "hidden" negative linear compressibility, in which NLC is absent at ambient pressure, switched on at 2 GPa and sustained up to the limit of our experiment, 5.5 GPa. Analysis of the changes in crystal structure using variable-pressure synchrotron X-ray diffraction reveals new chemical and geometrical design rules to assist the discovery of other materials with exciting hidden anomalous mechanical properties.
通过在包含两种不同支柱类型的酒架框架中首次解耦建筑单元的力学行为，我们表明L-酒石酸锂表现出负线性压缩性，其最大值K = -21 TPa，总体负线性压缩能力χ = 5.1%，这与迄今为止最特殊的材料相当。此外，分子支柱压缩和角度张开相互作用产生了所谓的“隐藏”负线性压缩性，即在环境压力下不存在负线性压缩性，在2 GPa时开启并持续到我们实验的极限5.5 GPa。使用可变压力同步加速器X射线衍射对晶体结构变化进行分析，揭示了新的化学和几何设计规则，以帮助发现具有令人兴奋的隐藏异常力学性能的其他材料。
