Determination of Absolute from Relative X-Ray Intensity Data

YÜapos;s letter1 on the determination of absolute from relative X-ray intensities suggests several interesting possibilities. His equations might be useful to anyone working with his synthesis2, but it is possible to devise a method not depending on the quantities αμh, which are not yet available. The ideal intensity of the hkl reflexion is given by where the f's are the structure factors and the x,y,z's the parameters of the atoms. Suppose that Ihkl is averaged for all reflexions in a given range of sin2θ. If λ/sin θ is small compared with the interatomic distances, the exponential terms in equation (1) will take on both positive and negative values, and their average over h,k,l will be practically zero. Then to a close approximation where the 's are the atomic structure factors for the centre of the range of sin2θ/λ2.