Acknowledgements. I thank colleagues at Berkeley, Cambridge and Durham for stimulating conversations; L. Moustakas for assisting with the use of image analysis software; R. Bouwens for providing code to manipulate stellar populations models; and D. Hogg for providing data in tabular form. This work has been supported by NASA grants.

With this study on KDP, we present an interface atomic structure determination of a crystal in contact with its growth solution. Using x-ray diffraction at a third-generation synchrotron radiation source, the structure of both the ͕101͖ and ͕100͖ faces has been determined. We found that the ͕101͖ faces are terminated by a layer of K 1 ions and not by H 2 PO 2 4 groups, resolving a long-standing issue that could not be predicted by theory. This result leads to an atomic-scale explanation of the influence of metal impurities on the macroscopic growth morphology. [S0031-9007(98)

We present a surface x-ray diffraction study on the KDP-water interface in which the structure of both the crystalline and liquid part of the interface has been measured. We have been able to determine the ordering components in the liquid in both the perpendicular and parallel directions. We find interface-induced ordering in the first four layers of water molecules. The first two layers behave icelike and are strongly bound to the surface. The next two layers are more diffuse and show only minor lateral and perpendicular ordering. Subsequent layers are found to behave similar to a bulk liquid.

No abstract

No abstract