Controlled Fabrication of DNA Molecular Templates for Formation and Measurement of Ultrathin Metal Nanostructures.

Fabrication of ultrathin metal nanostructures usually requires some combination of high-vacuum deposition and postgrowth processing, which precludes access to nanostructures of ultrasmall cross sections for most materials. DNA nanowires (NWs) are versatile insulating templates with intrinsic sub-10 nm line width. Here, we demonstrate a method of DNA template fabrication with precise control over the location and orientation of the DNA NWs.

Antiferroelectric Phase Transition in a Proton-Transfer Salt of Squaric Acid and 2,3-Dimethylpyrazine.

A proton-transfer reaction between squaric acid (Hsq) and 2,3-dimethylpyrazine (2,3-Mepyz) results in crystallization of a new organic antiferroelectric (AFE), (2,3-MepyzH)(Hsq)·HO (), which possesses a layered structure. The structure of each layer can be described as partitioned into strips lined with methyl groups of the MepyzH cations and strips featuring extensive hydrogen bonding between the Hsq anions and water molecules. Variable-temperature dielectric measurements and crystal structures determined through a combination of single-crystal X-ray and neutron diffraction reveal an AFE ordering at 104 K.