title: Negative linear compressibility in a crystal of α-BiB3O6.
abstract: Negative linear compressibility (NLC), a rare and important mechanical effect with many application potentials, in a crystal of α-BiB3O6 (BIBO) is comprehensively investigated using first-principles calculations and high-pressure synchrotron X-ray diffraction experiments. The results indicate that the BIBO crystal exhibits the second largest NLC among all known inorganic materials over a broad pressure range. This unusual NLC behaviour is due to the rotation and displacement of the rigid [BO3] and [BO4] building units that result in hinge motion in an umbrella-like topology. More importantly, the parallel-polar lone-pair electrons on the Bi(3+) cations act as "umbrella stands" to withstand the B-O hinges, thus significantly enhancing the NLC effect. BIBO presents a unique example of a "collapsible umbrella" mechanism for achieving NLC, which could be applied to other framework materials with lone-pair electrons.
authors: Beijing Center for Crystal R&D, Key Lab of Functional Crystals and Laser Technology of Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.|University of Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Lei
authors: L
authors: Kang
authors: Beijing Center for Crystal R&D, Key Lab of Functional Crystals and Laser Technology of Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.|University of Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Xingxing
authors: X
authors: Jiang
authors: Beijing Center for Crystal R&D, Key Lab of Functional Crystals and Laser Technology of Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Siyang
authors: S
authors: Luo
authors: Beijing Center for Crystal R&D, Key Lab of Functional Crystals and Laser Technology of Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.|University of Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Pifu
authors: P
authors: Gong
authors: School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, PR China.
authors: Wei
authors: W
authors: Li
authors: School of Earth and Space Sciences, Peking University, Beijing, 100871, PR China.
authors: Xiang
authors: X
authors: Wu
authors: Beijing Synchrotron Radiation Facility, Institute of High Energy Physics Chinese Academy of Science, Beijing, 100049, PR China.
authors: Yanchun
authors: Y
authors: Li
authors: Beijing Synchrotron Radiation Facility, Institute of High Energy Physics Chinese Academy of Science, Beijing, 100049, PR China.
authors: Xiaodong
authors: X
authors: Li
authors: Beijing Center for Crystal R&D, Key Lab of Functional Crystals and Laser Technology of Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Chuangtian
authors: C
authors: Chen
authors: Beijing Center for Crystal R&D, Key Lab of Functional Crystals and Laser Technology of Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Zheshuai
authors: Z
authors: Lin