Rotational Spectrum of Dichloromethane–Ne: Internal Dynamics and Cl Quadrupolar Hyperfine Effects

none 4 no The rotational spectra of three isotopologues, CH235Cl2···20Ne, CH235Cl37Cl···20Ne, and CH235Cl2···22Ne, of the complex dichloromethane-neon have been assigned and measured by molecular beam Fourier transform microwave spectroscopy. The corresponding tunnelling splittings-due to the motion of Ne from above to below the ClCCl plane-have been determined as E0+0- = 6.8900(5), 6.6630(4), and 6.3724(7) MHz, respectively. From these data the barrier to planarity has been obtained, B2 = 68.7 cm-1. In addition, the structure and the 35Cl (or 37Cl) quadrupole coupling constants have been determined. Favero, Laura B.; Maris, Assimo; Paltrinieri, Laura; Caminati, Walther Favero, Laura B.; Maris, Assimo; Paltrinieri, Laura; Caminati, Walther