Piperazine silicate (EU 19): the structure of a very small crystal determined with synchrotron radiation

Abstract

Single-crystal diffraction data have been recorded for a very small crystal of dimensions 8 x 18 × 175 ~rn 3. From these data the structure of piperazine silicate (EU 19) has been determined and refined to R = 0.094 for 490 observed reflections. Data collection for such a crystal has been made practicable by the high intensity of the Daresbury Synchrotron Radiation Source and the Enraf-Nonius FAST area detector diffractometer. The potential of this synchrotron radiation method for other small crystals including proteins is discussed.

Layered zeolitic materials: an approach to designing versatile functional solids

“…Inside this family, the Nu-6(1) is the most relevant zeolitic precursor synthesized from hydrothermal conditions in presence of 4,4'-bipyridil molecules as template which are localized in two crystallographically different positions (Figure 8a). 53, The structure of the Nu-6(1) precursor is similar to those previously described for layered silicates so-called EU-19 and MCM-69 (Table 1), 54,55 although the interlayer space in these last precursors is lower due to the shorter size of the hosted molecules, favoring modifications in After thermal treatment for SDA removing in the Nu-6(1), the small-pore pentasil Nu-6(2) zeolite is obtained by layers condensation, being this 3D microporous zeolite characterized by a one-dimensional channel system of two independent and non-equivalent sets of 8 MRs which alternate along the crystallographic axis c (named as A and B in Figure 8b). 56,57 It is notorious the close structural relation between Nu-6(2) and the orthorhombic cesium aluminosilicate EU-20 (IZA code CAS), being both built by applying different symmetries to the same pentasil periodic building unit (Figure 8c).…”

Structural aspects of metal-organic framework-based energy materials research at Diamond

“…Prior to this, for example, nonmacromolecular single crystal studies using synchrotron radiation were rare and depended on gaining occasional access to beamlines dedicated to other applications [1,2,40].…”

“…Although we made some earlier use of the Daresbury Synchrotron Radiation Source (SRS) [1,2], our sustained use of synchrotron facilities began in 1997 with the inauguration of the pioneering small-molecule singlecrystal SRS Station 9.8. Our single-crystal work on Stations 9.8 and 16.2SMX (e.g.…”

Trends and Challenges in Experimental Macromolecular Crystallography

“…where f t is the atomic number of the ith atom type, nj is the number of atoms of that type in the unit cell out of a total of N types, V x is the sample volume, and V o is the unit cell volume (Andrews et al 1988). From this formula different crystal volumes and types of crystal can be compared (e.g.…”