Direct phase determination for quasi-kinematical electron diffraction intensity data from organic microcrystals.

Direct phasing techniques using cosine estimates for three-phase and four-phase structure invariants in space group P1 are applied to zonal hk0 electron diffraction intensity data from an orthorhombic paraffin and a cephalin. Ab initio use of these kinematical phases is shown to derive the correct structures of the methylene subcell packings for these compounds in agreement with earlier determinations from Patterson maps.