The liquid structure of haloforms CHCl3 and CHBr3

New neutron and x-ray diffraction measurements are reported on liquid chloroform, CHCl(3), and bromoform, CHBr(3). Experimental total scattering structure factors have been interpreted by the reverse Monte Carlo method of structural modelling. Partial radial distribution functions, intramolecular bond angle distributions and functions characterizing distance-dependent orientational correlations have been calculated directly from the particle coordinates. It has been found that most of these characteristics of the microscopic structure can be approximated rather well by functions calculated for hard sphere like reference systems. The two liquids show similar features from the point of view of their structure. There are also some distinctive features in terms of orientational correlations: nearest neighbour molecules prefer face-to-face arrangement in chloroform whereas in bromoform, edge-to-face configurations dominate, with a significant occurrence of corner-to-face type correlations.