Vibrational Spectra and Molecular Vibrational Behaviors of Dibenzyl Disulfide, Dibenzyl Sulphide and Bibenzyl

Abstract

The vibration spectroscopy (Raman and infrared) of widely concerned molecules in sulfur corrosion phenomenon (Dibenzyl Disulfide, Dibenzyl Sulphide, and Bibenzyl) is detailedly analyzed based on density functional theory and experimental measurement. The dominant conformations of these molecules are determined according to Boltzmann distribution in relative Gibbs free energy. Additionally, noncovalent interaction analysis is conducted to indicate intramolecular interaction. Vibration normal mode is assigned based on potential energy distribution, which comprehensively reveals the molecular vibrational behaviors. Conformations weighted spectra are obtained and compared with experimentally measured spectra. We found that experimental spectra are in good agreement with the theoretical spectra in B3LYP-D3(BJ)/6-311G** level with a frequency correction factor. Furthermore, the divergence among these molecules is discussed. The vibrational behavior of the methylene group in the molecule shows a trend with the presence of the sulfur atom.

Electronic and optical properties of lead‐free double perovskites A2BCl6 (A = Rb, Cs; B = Si, Ge, Sn) for solar cell applications: A systematic computational study

“…Precise identification of the vibrational groups and kinds that pertain to the standard mode is challenging. [ 75 ] The IR and RAMAN spectra for the studied compounds have been depicted in Figure 5. There are a total of 21 vibrational modes found for A 2 BX 6 .…”

Phase Transitions and Stabilities among Three Phases of Di-p-tolyl Disulfides

“…From the literature, four normal modes were seen at high frequencies of 3083 cm −1 , 3052 cm −1 , 3043 cm −1 , and 2943 cm −1 . All of the modes were contributed to by C–H stretching vibrations [ 54 ]. Their corresponding calculated absorption frequencies of phases α, β, and γ are provided in Table 2 .…”

“…Their corresponding calculated absorption frequencies of phases α, β, and γ are provided in Table 2 . There is a large frequency difference between absorption peaks of 2943 cm −1 , and 1596 cm −1 , which is because of the high force constant for stretching vibrations [ 54 ]. Furthermore, energy for stretching vibration is higher than torsion and bending energy, therefore most stretching vibration modes occur at high frequencies.…”

“…The bending of the H atom on the benzene ring corresponds to modes observed at 1494 cm −1 , 1452 cm −1 , 1139 cm −1 , and 1068 cm −1 taken from experimental work [ 54 ]. The corresponding frequencies and modes for phases α, β, and γ are given in Table 2 .…”