7 The Setup:X-ray Source: x-ray tubes, rotating anode tubes, or particle storage ringsGonoimeterDetectors: X-ray films, CCD cameras, or Multiwire detectors.CHESS at Cornell is an example of a particle storage ring.Usually produce X-rays by bombarding Cu or Mb with electrons produced by a heated filament and accelerated in an electric field.When electron knocked out of low energy level, another falls and fills its space, emitting and x-ray photon.Multiwire detectors are lots of anode and cathode wires crisscrossing that pick up the x-ray signal.CCD camera set up so x-rays hit a phosphor face plate which then emits photons picked up by an optical detector.
8 How Does X-Ray Crystallography Work ? Image of diffraction
11 From diffraction to electron density map Fourier TransformTo get from the diffraction pattern to the electron density, you have to use a Fourier Transform.A transform is an eqn that transforms a function with some variables into a function with reciprocal variables. It is a way of going from the reciprocal lattice to the real lattice.
13 Resolution Resolution: another measure of how good your model is. Resolution gives the size of the smallest molecule you can see or resolve.Dependent on the amount of data ultimately phased and used in structure determination.
14 The Final Result A PDB coordinate file ORIGX TRX 147ORIGX TRX 148SCALE TRX 149SCALE TRX 150SCALE TRX 151ATOM N SER A TRX 152ATOM CA SER A TRX 153ATOM C SER A TRX 154ATOM O SER A TRX 155ATOM CB SER A TRX 156ATOM OG SER A TRX 157ATOM N ASP A TRX 158ATOM CA ASP A TRX 159ATOM C ASP A TRX 160ATOM O ASP A TRX 161ATOM CB ASP A TRX 162A PDB coordinate file