Orientational correlations and hydrogen bonding in liquid hydrogen chloride

Neutron diffraction data, obtained by employing the hydrogen isotope substitution technique, on orthobaric hydrogen chloride at two state points are presented. The site-site radial distribution functions are derived from these data and are compared with similar results obtained previously for hydrogen iodide and hydrogen bromide. Comparison of the measured hydrogen-hydrogen and chlorine-hydrogen radial distribution functions with those derived assuming uncorrelated orientations demonstrates the presence of strong orientational correlations between first neighboring HCl molecules at both states. An analysis of molecular configurations compatible with the experimental data as generated by a Monte Carlo simulation routine is used to discuss the extent of hydrogen bonding in liquid HCl. (C) 1997 American Institute of Physics.