Volume III/27 covers the magnetic properties of non-metallicinorganic compounds based on transition elements. It cantherefore be considered as a supplement to volumes III/4(1970) and III/12 (1978-82) and as a counterpartto volumeIII/19, in which the magnetic properties of metals, alloysandmetallic compounds are compiled. III/27j deals withhalides. In the present subvolume III/27j1 data are compiledfor the halides having the general chemical formula MXn,where M represents a 3d-element and X a halogen element.Also graphite compounds intercalated by these transitionmetal chlorides have been included.