Soft X-Ray Diffraction up to Wavelengths of 6.0Å Becomes Feasible at ID1 of ESRF

nce b Euro p ean Sync hro tro n Radi ati on Facil i ty (ESR F) G reno bl e, Fra nce c Euro p ean Mo l ecular Bi ol ogy La b ora to ry (EMBL) G reno bl e, Fra nce d G KSS Forschung szentru m , Geesthacht, G erm anyRecent ex per iment s carrie d out at the A noma lous Scatterin g Beamline ID 1 of ESR F are descri bed w hich show that a cold helium atmosphere pro vides optimal condition s for protein crystallogra phy with soft X -rays at w avelengths up to 6 ¡ A .Image plates are suitable detectors for this wavelength range.T he impro vement with resp ect to earlier exp eriments is considerable .T his observ ation op ens the w ay to the use of anomalous disp ersion at the K -edge of light elements , li ke phosphorus, sulphur, chlorine and calcium.Moreo ver, there is an interest to use the strong anomalous disp ersion of some heavy elements such as uranium (11 0 anomalous electron units at its M V edge) to solve large biologi cal structures.T he metho ds of multiw avelength anomalous di˜ractio n and di˜raction anomalous Ùne structure Ùnd new resonant lab els w hich are w ide spread in livin g matter and materials.