摘要
面对高精尖仪器或设备的热膨胀控制的需求,探索新的负热膨胀材料显得尤为重要.本文采用"平均原子晶格体积"概念预测各向异性新的负热膨胀材料体系,据此发现了REFe(CN)_(6)(RE=La,Sm,Ho,Lu)负热膨胀材料家族.我们采用原位中子粉末衍射(NPD)、X射线吸收精细结构谱(EXAFS)和第一性原理计算揭示了其负热膨胀来源于低频声子振动模式中的CN原子的横向热振动,进一步发现"平均原子晶格体积"越大,其对应的低频声子模式频率越低,格林艾森常数越负,CN原子的横向热振动越强.本工作为定性预测负热膨胀材料提供了新的方法,对热膨胀控制与设计具有重要意义.
Negative thermal expansion(NTE),as an abnormal physical behavior,has been followed by scientists’attention over the past 30 years,due to its fascinating physical mechanisms and the prospect of high-precision thermal expansion control[1-5].Although some NTE materials(alloys[6],cyanides[7],fluorides[8-10],nitrides[11],oxides[12,13],MOFs[14-16],etc.)have been found,their number and variety are still very small,limiting their applications.Exploring and designing new NTE materials is an important and challenging topic for the development of the field of NTE.Researchers have been continually reviewing and summarizing obtained results to look to the future of NTE[17-23].
作者
高其龙
孙强
Alessandro Venier
Andrea Sanson
Qingzhen Huang
贾瑜
梁二军
陈骏
Qilong Gao;Qiang Sun;Alessandro Venier;Andrea Sanson;Qingzhen Huang;Yu Jia;Erjun liang;Jun Chen(Key Laboratory of Materials Physics of Ministry of Education,and School of Physics and Microelectronics,Zhengzhou University,Zhengzhou 450052,China;Beijing Advanced Innovation Center for Materials Genome Engineering,School of Mathematics and Physics,Department of Physical Chemistry,University of Science and Technology Beijing,Beijing 100083,China;Department of Physics and Astronomy,University of Padova,Padova I-35131,Italy;NIST Center for Neutron Research,National Institute of Standards and Technology,Gaithersburg MD,20899-6102,United States;Key Laboratory of Special Functional Materials of Ministry of Education of China,and School of Materials Science and Engineering,Henan University,Kaifeng 475004,China)
基金
supported by the National Natural Science Foundation of China(22071221,21905252,21825102 and 11774078)
the Natural Science Foundation of Henan Province(212300410086)
the Innovation Scientists and Technicians Troop Construction Projects of Henan Province(10094100510025)
supported by the National Supercomputing Center in Zhengzhou
providing beamtime at the XAFS beamline(Experiment n.20185177)。
