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arXiv · 1804.07551

Density Functional Studies Reveal Anomalous Lattice Behavior in Metal Cyanide, AgC8N5

Baltej Singh·Mayanak K. Gupta·Ranjan Mittal·Samrath L. Chaplot
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Abstract

We have investigated anomalous lattice behavior of metal organic framework compound AgC8N5on application of pressure and temperature using ab-initio density functional theory calculations. The van der Waals dispersion interactions are found to play an important role in structural optimization and stabilization of this compound. Our ab-initio calculations show negative linear compressibility (NLC) along the c-axis of the unit cell. The ab-initio lattice dynamics as well as the molecular dynamics simulations show large negative thermal expansion (NTE) along the c-axis. The mechanism of NLC and NTE along the c-axis of the structure is governed by the dynamics of Ag atoms in the a-b plane. The NLC along the c-axis drives the NTE along that direction.

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Baltej Singh, Mayanak K. Gupta, Ranjan Mittal, Samrath L. Chaplot. 2018-04-20. Density Functional Studies Reveal Anomalous Lattice Behavior in Metal Cyanide, AgC8N5. https://arxiv.org/abs/1804.07551

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