Infrared spectroscopic studies on the cluster size dependence of charge carrier structure in nitrous oxide cluster anions

Growth, Hirshfeld surfaces, spectral, quantum chemical calculations, photoconductivity and chemical etching analyses of nonlinear optical p-toluidine p-toluenesulfonate single crystal

A single crystal of p-toluidine p-toluenesulfonate (PTPT) has been grown by slow evaporation solution technique (SEST) at room temperature. Single crystal X-ray analysis confirms that grown crystal belongs to the monoclinic structure with space group P2₁. Intermolecular interactions and fingerprint plots of PTPT molecules are executed by Hirshfeld surface analysis. It was found that H···H (44.2%) contacts have maximum intermolecular interactions contributions in the total Hirshfeld surface area. The characteristic absorption band occurs at below 290 nm. The functional groups were identified using FTIR and FT-Raman analyses and compared with theoretical values. The title molecule contains fourteen CH bonds and three OH bonds. The calculated HOMO and LUMO energy values are -6.125 eV and -1.157 eV, respectively. The chemical potential (μ) and electronegativity (χ) values are estimated to be -3.4938 eV and 3.4938 eV, respectively. The strongest negative hyperconjugation occurs due to the charge transfer from the occupied orbital (σ) to the unoccupied orbital (π*) which is calculated for the σ(N20-C21) → π*(N20-O18). The green and red lines in the total density of states (TDOS) spectrum indicate the occupied orbital and virtual orbital levels, respectively. Photoconductivity studies have been done for the grown crystal. It is observed that the dark current is greater than photocurrent. It shows negative photoconductivity nature of PTPT crystal. The etching analysis was executed on (001) plane of PTPT crystal. It has rectangular shape etch pits patterns.

Lewis Acid-Mediated One-Electron Reduction of Nitrous Oxide

The one-electron reduction of nitrous oxide (N₂ O) was achieved using strong Lewis acids E(C₆ F₅ )₃ (E=B or Al) in combination with metallocenes. In the case of B(C₆ F₅ )₃ , electron transfer to N₂ O required a powerful reducing agent such as Cp*₂ Co (Cp*=pentamethylcyclopentadienyl). In the presence of Al(C₆ F₅ )₃ , on the other hand, the reactions could be performed with weaker reducing agents such as Cp*₂ Fe or Cp₂ Fe (Cp=cyclopentadienyl). The Lewis acid-mediated electron transfer from the metallocene to N₂ O resulted in cleavage of the N-O bond, generating N₂ and the oxyl radical anion [OE(C₆ F₅ )₃ ]^⋅- . The latter is highly reactive and engages in C-H activation reactions. It was possible to trap the radical by addition of the Gomberg dimer, which acts as a source of the trityl radical.