1
|
Jiang P, Neuefeind JC, Avdeev M, Huang Q, Yue M, Yang X, Cong R, Yang T. Unprecedented lattice volume expansion on doping stereochemically active Pb 2+ into uniaxially strained structure of CaBa 1-xPb xZn 2Ga 2O 7. Nat Commun 2020; 11:1303. [PMID: 32161268 PMCID: PMC7066146 DOI: 10.1038/s41467-020-14759-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 01/31/2020] [Indexed: 11/09/2022] Open
Abstract
Lone pair cations like Pb2+ are extensively utilized to modify and tune physical properties, such as nonlinear optical property and ferroelectricity, of some specific structures owing to their preference to adopt a local distorted coordination environment. Here we report that the incorporation of Pb2+ into the polar “114”-type structure of CaBaZn2Ga2O7 leads to an unexpected cell volume expansion of CaBa1-xPbxZn2Ga2O7 (0 ≤ x ≤ 1), which is a unique structural phenomenon in solid state chemistry. Structure refinements against neutron diffraction and total scattering data and theoretical calculations demonstrate that the unusual evolution of the unit cell for CaBa1-xPbxZn2Ga2O7 is due to the combination of the high stereochemical activity of Pb2+ with the extremely strained [Zn2Ga2O7]4− framework along the c-axis. The unprecedented cell volume expansion of the CaBa1−xPbxZn2Ga2O7 solid solution in fact is a macroscopic performance of the release of uniaxial strain along c-axis when Ba2+ is replaced with smaller Pb2+. Lone pair cations can impart interesting features in some structures, such as noncentrosymmetry. Here the authors show unexpected cell volume expansion in a polar “114”-type oxide upon replacing Ba2+ with a smaller Pb2+, and attribute it to high stereochemical activity of Pb2+ with the strained framework.
Collapse
Affiliation(s)
- Pengfei Jiang
- College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 401331, P. R. China
| | - Joerg C Neuefeind
- Chemical and Engineering Materials Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Maxim Avdeev
- Australian Nuclear Science and Technology Organization, Lucas Heights, NSW, 2234, Australia.,School of Chemistry, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Qingzhen Huang
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Mufei Yue
- College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 401331, P. R. China
| | - Xiaoyan Yang
- College of Materials Science and Engineering, Guilin University of Technology, Guilin, Guangxi, 541004, P. R. China
| | - Rihong Cong
- College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 401331, P. R. China
| | - Tao Yang
- College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 401331, P. R. China.
| |
Collapse
|