RESUMEN
Enantiomers are ubiquitous in many areas of science, such as pharmaceuticals, agriculture, and food. Nuclear magnetic resonance (NMR) alone is not able to differentiate enantiomers as their spectra are identical. However, these can be distinguished using chiral auxiliaries (such as chiral complexing agents) that form diastereomeric complexes, but absolute identification is still troublesome, usually requiring a chemical reaction with a chiral derivatizing agent. Here, we propose a new method that uses a hybrid mixture of solvating agents in a simple comparison of diffusion NMR experiments, which can discriminate enantiomers in both frequency and diffusion domains, dubbed CHIMERA (CHIral Micelle Enantiomer Resolving Agent). The new method was assessed for twenty-three small chiral molecules using a combination of BINOL and (-)-DMEB, a chiral surfactant, and initial results indicate that absolute configuration can be obtained from a simple experiment.
RESUMEN
The electronic transport anisotropy for different C-doped borophene polymorphs (ß12andχ3) was investigated theoretically combining density functional theory and non-equilibrium Green's function. The energetic stability analysis reveals that B atoms replaced by C is more energetically favorable forχ3phase. We also verify a directional character of the electronic band structure on C-doped borophene for both phases. Simulated scanning tunneling microscopy and also total density of charge confirm the directional character of the bonds. The zero bias transmission forß12phase atE-EF= 0 shows that C-doping induces a local current confinement along the lines of doped sites. TheI-Vcurves show that C-doping leads to an anisotropy amplification in theß12than in theχ3. The possibility of confining the electronic current at an specific region of the C-doped systems, along with the different adsorption features of the doped sites, poses them as promising candidates to highly sensitive and selective gas sensors.