Zero area thermal expansion of honeycomb layers via double distortion relaxation in (PPh4)[Cu2(CN)3]

The zero area thermal expansion (TE) of a cyanide-bridged honeycomb layer was demonstrated by (PPh4)[Cu-2(CN)(3)] (PPh4+ = tetraphenyl phosphonium) via double distortion relaxation. This characteristic TE behaviour involves in-plane anisotropy of the distorted layer with positive and negative TE. The conformation change in distorted PPh4+ tetrahedrons also occurred between the layers. This was coupled with the anisotropic TE of the layers in accordance with complementary structural changes in the cation and anion counterparts.

Automated summary

This article presents the unique thermal expansion behavior of a cyanide-bridged honeycomb layer material, including zero thermal expansion, in-plane anisotropy, and complementary structural changes in the cation and anion counterparts.