Collisional cross-section of water molecules in vapour studied by means of 1 H relaxation in NMR

摘要: In gas phase, collisions that affect the rotational angular momentum lead to return of magnetization its equilibrium (relaxation) in Nuclear Magnetic Resonance (NMR). To best our knowledge, longitudinal relaxation rates R1 = 1/T1 protons H2O and HDO have never been measured phase. We report R1 phase a field 18.8 T, i.e., at proton Larmor frequency ν0 = 800 MHz, temperatures between 353 373 K pressures 9 101 kPa. By assuming spin rotation is dominant mechanism, we estimated effective cross-section σJ for transfer due H2O-H2O HDO-D2O collisions. Our results allow one test theoretical predictions intermolecular potential water