Theoretical studies of the methyl rotational barrier in toluene

Precise Spectroscopic [IR, Raman and NMR] Investigation and Gaussian Hybrid Computational Analysis (UV-Visible, NIR, MEP Maps and Kubo Gap) on L-Valine

“…The C-CH 3 in-plane bending vibration is found at 340 cm -1 and out-of-plane bending vibration is found at 260 cm -1 . As reported in the literature [29,30], all the above C-CH 3 vibrations deviated much from the expected range. This is purely due to the repulsion between methyl groups.…”

Experimental and Quantum Chemical Calculations of 2-Amino-4,5,6,7-Tetrahydrobenzo[b]Thiophene-3-Carbonitrile

“…The N-H in-plane bending vibrations (scissoring) are usually observed in the region of 1610-1630 cm −1 , rocking vibrations are assigned in the range of 1100-1200 cm −1 and the out of plane bending (wagging and twisting) vibrations are normally identified under 900 cm −1 [28][29][30][31]. In this case, in plane bending mode δ HNH was observed at 1616/1618 cm −1 (FT-IR/FTRaman) and was calculated to be at 1581 cm −1 by scaled B3LYP.…”

Communication: Molecular gears

“…This methyl group occupies a position of highest potential energy with one CH bond in the molecular plane, and one CH bond above and one below the plane. 3 However, the configuration with one CH bond above (in a plane perpendicular to the benzene ring) and two CH bonds below the plane lies only 14.0 ± 0.3 cal/mol lower. [3][4][5] Clearly, a methyl rotation over π leads to an identical situation energetically.…”