Molecular Motion in Liquids: On the Prevalence of Large‐Size Rotational and Translational Diffusion Steps

摘要: It is shown experimentally (Fourier inversion of vibrational band contours) that the molecular orientational motion in some representative common liquids [methylene chloride (CH2Cl2), methyl iodide (CH3I), chloroform (CHCl3), cyclohexane (C6H12)] appears to consist angular jumps order 20° 60°. During a jump, which completed times 0.4 × 10−12 sec, molecules are observed rotate as if they were their vapor phase, regardless whether or not involves tilting permanent dipole moment size molecule. The infrared data compared with results from nuclear magnetic relaxation studies. seen rotational liquids, it by these techniques, sensitive association, weak hydrogen bonding, etc. On basis extended Torrey model intermolecular spin–lattice relaxation, translational diffusion large variety them strongly associated, occurs jump diameter after trapping time 10−11–10−10 sec. As far can be predicted, obey classical very small steps would exception rather than rule. possibility discussed dimer diffusing entity acetic acid.