Similar to what occurs in biological systems; irreversible replacement of potassium with thallium in coordination polymer nanostructures

Irreversible solid-state structural transformation of two-dimensional KI coordination polymer nanostructures, prepared by sonochemical procedure, to one-dimensional TlI coordination polymer nanoparticles has been observed upon mechanochemical reaction of compound [K(dcpa)(H2O)0.5]n (1), [Hdcpa = 2,4-dichlorophenoxyacetic acid] with TlNO3. This irreversible exchange is similar to that occurred in biological systems approved the toxicity of thallium. In addition to removal of coordinated H2O molecule, during this transformation the coordination bonds of 2-chloro substituent and phenoxy oxygen atom of dcpa− with the potassium ion was broken. The bridging and chelating coordination behavior of dcpa− between three K(I) ions in 1 is changed to bridging coordination behavior of dcpa− between two Tl(I) ions in [Tl(μ2-dcpa)]n (2). A comparison between crystal data of these two compounds shows that these two compounds have the same crystal system and similar space groups, unit cell dimensions and volume. This similarity may be an assistant factor for possibility of this solid-state conversion.

Graphical AbstractIrreversible solid-state structural transformation of 2D KI coordination polymer nanostructures to 1D TlI coordination polymer nanoparticles has been observed upon mechanochemical reaction potassium polymer with TlNO3. This irreversible exchange is similar to what occurs in biological systems approved the toxicity of thallium.Figure optionsDownload full-size imageDownload as PowerPoint slide