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Updated: Dec 14, 2025
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Effect of bond on negative thermal expansion of Prussian blue analogues MCo(CN)6(M=Fe, Ti and Sc): a first-principles
Yuan Li1, Qilong Gao1, Dahu Chang2
1Key Laboratory of Materials Physics , Ministry of Education International Laboratory for Quantum Functional Materials of Henan, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450001, People's Republic of China.
Abstract:
Negative thermal expansion (NTE) is an abnormal physical behavior that has promising applications for high precision thermal control. Since Prussian blue analogues have the two central linking atoms of -C≡N-, they have large structure flexibility and are suitable to explore new NTE materials. However, understanding the nature of structure flexibility from the point of view of chemical bonding is important and urgent. Here, we adopt for the first time first-principles calculations to predict that the cubic TiCo(CN)6and ScCo(CN)6have NTE behavior. The calculated results for M in MCo(CN)6(M = Fe, Ti and Co) indicated that the Sc-N bond is the strongest, but with the weakest direction dependence among the M-N bonds in the three systems. The lattice dynamics calculations results revealed that the low-frequency phonon vibration modes for NTE in MCo(CN)6have much stronger relationship with the M-N bond feature. The present work reveals the important role of the related bond in the NTE open-framework materials.
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