Unusual Surface Texture, Dimensions and Morphology Variations of Chiral and Single Crystals*.

We demonstrate here a unique metallo-organic material where the appearance and the internal crystal structure are in contradiction. The egg-shaped (ovoid) crystals have a brain-like texture. Although these micro-sized crystals are monodispersed; like fingerprints their grainy surfaces are never exactly alike. Remarkably, our X-ray and electron diffraction studies unexpectedly revealed that these structures are single-crystals comprising a continuous coordination network of two differently shaped homochiral channels. By using the same building blocks under different reaction conditions, a rare series of crystals have been obtained that are uniquely rounded in their shape. In stark contrast to the brain-like crystals, these isostructural and monodispersed crystals have a comparatively smooth appearance. The sizes of these crystals vary by several orders of magnitude.