INSITU SURFACE X-RAY-DIFFRACTION USING HIGH-ENERGY SYNCHROTRON RADIATION - STUDIES OF THE ADP(100) AND ADP(101) GROWTH INTERFACES UNDER AQUEOUS-SOLUTION FLOW CONDITIONS

The necessity, in terms of understanding and utilizing crystal growth theory, for information concerning the structural nature of the growth interface during crystallization from the solution phase is outlined and discussed together with a description of a novel in situ growth ce ll which enables optical microscopy and surface x-ray diffraction to b e carried out simultaneously. Using the cell, preliminary surface diff raction data have been recorded from the {101} and {100} crystal/solut ion interfaces of nearly perfect crystals of ammonium dihydrogen ortho phosphate during growth and dissolution experiments under aqueous solu tion flow conditions. The measurements of the x-ray rocking curves dur ing the growth of these faces provide further evidence that the x-ray diffraction peak width depends on the growth conditions and that this technique is capable of assessing structural changes in the crystal su rface during growth. The potential development of this and other relat ed techniques are outlined together with expected future trends.