Silicon amino acids

Abstract

The existence and gas phase stability of silicon analogues of three natural amino acids (i.e., silicon glycine, silicon alanine, and silicon valine) belonging to the novel class of compounds termed silicon amino acids (SiAA) are investigated theoretically on the basis of ab initio QCISD/aug‐cc‐pVTZ and MP2/aug‐cc‐pVTZ calculations. All molecules studied (in their gas phase canonical forms) are structurally comparable to their proteinogenic counterparts (i.e., glycine, l‐alanine, and l‐valine) and capable of forming several structural isomers as such. These higher energy isomers are characterized by small relative energies (not exceeding 4 kcal mol−1). The simulated IR spectra of the Si‐Gly, Si‐Ala, and Si‐Val global minima are also presented and discussed.

Superacidic Properties of Protonated PtFn (n = 1–6) and Their Ability to Form Supersalts: DFT Study

“…The calculated deprotonation energy of HPtF 6 is comparable to the deprotonation energy of the strongest superacid, HSbF 6 , and less than the deprotonation energy of HAuF 6 . [46,47] The calculated deprotonation energy of HPtF 6 is well-matched with the previously reported value. [48] The calculated deprotonation energy of HPtF 4 is comparable to the corresponding reported value of HTaF 6 ; however, HPtF 5 is more acidic than HTaF 6 .…”