STRUCTURE FACTOR AMPLITUDE AND PHASE DETERMINATION BY A NEW 2 BEAM DIFFRACTION INTERFERENCE METHOD

A method to measure the Amplitude and phase of the Fourier transform o f the electron density function of complex materials is proposed. The method is based on the measurement of the interference between pairs o f diffracted beams produced by two coherent non-collinear incident X-r ay beams. The method is applicable to 2 dimensional crystals and 3 dim ensional crystals with unit cells larger than about 80 angstrom. This method may open the way to a more direct determination of the structur e of complex biological molecules.