Biaxial negative thermal expansion in Zn[N(CN)₂]₂

Abstract

A 2D-layered network Zn[N(CN)2]2, is reported in which the transverse vibrations of C atoms and the rotation of ZnN4 tetrahedra dominate its biaxial NTE behavior.

Exploring negative thermal expansion materials with bulk framework structures and their relevant scaling relationships through multi-step machine learning

“…These suggest that our ML predicted NTE materials are reasonable and reliable. It is worth mentioning that our predicted NTE material Zn[N(CN) 2 ] 2 with CNTE of −18.7 × 10 −6 K −1 was experimentally validated in a recent work, 162 and the measurement results of CNTE is about −12.0 × 10 −6 K −1 . Two results show that they coincided well.…”

Giant anisotropic thermal expansion of copper-cyanido flat layers with flexible copper nodes

“…9,10 The motif of layer structures such as flat and undulation significantly influences on the anisotropic structural transformation. For example, undulating layers in uniaxial 11,12 and bi-axial [13][14][15][16] directions are highly flexible due to the anisotropic and isotropic structural transformations, respectively, involving layer-expansion/contraction (Fig. 1).…”