POWDER DIFFRACTION FROM COMPRESSED MOLECULAR-HYDROGEN IN A DIAMOND-ANVIL CELL

We report the first observation of x-ray powder-diffraction from molec ular hydrogen in a diamond-anvil cell obtained at the European Synchro tron Radiation Facility using image-plate recording techniques. The sa mple was prepared by compression of hydrogen together with nickel powd er in the high-pressure chamber. This result suggests that structural phase transitions in solid hydrogen could be studied directly with pow der x-ray techniques. (C) 1997 American Institute of Physics.