Structural Transition in the Perovskite-like Bimetallic Azido Coordination Polymers: (NMe4)2[B′·B″(N3)6] (B′ = Cr3+, Fe3+; B″ = Na+, K+)

• Published in: Crystal growth & design 2014-08, Vol.14 (8), p.3903-3909
• Main Authors: Du, Zi-Yi, Zhao, Ying-Ping, He, Chun-Ting, Wang, Bao-Ying, Xue, Wei, Zhou, Hao-Long, Bai, Jie, Huang, Bo, Zhang, Wei-Xiong, Chen, Xiao-Ming
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder; Cross-disciplinary physics: materials science; rheology; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; General studies of phase transitions; Materials science; Order-disorder and statistical mechanics of model systems; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Thermal expansion; thermomechanical effects and density; Thermal properties of condensed matter; Thermal properties of crystalline solids
• ISSN: 1528-7483; 1528-7505
• DOI: 10.1021/cg5004676

Through in situ variable-temperature single-crystal X-ray diffraction analysis, a solid–solid structural phase transition induced by the successive displacements of the [NMe4]+ guest and a subsequent abrupt order–disorder transform for both the cationic guest and the cage-like framework was tracked in four perovskite-like bimetallic azido coordination polymers: (NMe4)2­[B′·B″(N3)6] (B′ = Cr3+, Fe3+; B″ = Na+, K+). Such structural transition was also confirmed by differential scanning calorimeter measurement, variable-temperature powder X-ray diffraction analysis, and variable-temperature dielectric permittivity measurement, as well as molecular dynamics simulation. Conclusively, these compounds provide a good host–guest model for understanding and modulating the thermal motion behavior of the [NMe4]+ guest in various confined spaces constructed by the perovskite-like azido frameworks.