THE HIGHLY RESOLVED EXCESS ELECTRON DISTANCE DISTRIBUTION OF BIOPOLYMERS IN SOLUTION - CALCULATION FROM INTERMEDIATE-ANGLE X-RAY-SCATTERING AND INTERPRETATION

A procedure is proposed for calculation of the high-resolution p(r) function at distances greater than 0.4 nm. To reduce termination errors in the distance distribution function, the difference between the scattered intensity of the molecule, calculated using atomic coordinates, and the scattered intensity of the 'independent' atoms of the macromolecule is modified by a Hamming window and then Fourier transformed. A more direct structural interpretation of changes in the highly resolved p(r) function is possible by the correlation of known structural elements in proteins and nucleic acids with main features of the electron distance distribution function via the so-called distance plot.