CrysTallograPhy in soUTh-easTern eUroPe


active molecules and their interactions, the Laboratory for Chemical and Biological Crystallography was founded in 1997 for research with protein crystallography. Structures of enzymes complexed with substrates and inhibitors are revealing catalytic mechanisms at the molecular level by combining structural, biochemical and genetic methods of analysis.


Powder Diffraction at RBI, Zagreb By


Stanko PoPović (spopovic@phy.hr) Powder diffraction is used in the laboratory for analysis of


Co-crystals of cholic acid (CA) with n-alkylammonia (n = 10, 12, 14, 16) represent first examples of CA’s co-crystals with molecules of comparable size. In one of the compounds a completely new type of bilayer arrangement was found (upper right). (V. Tomašić, Z. Štefanić, CrystEngComm 9 (2007) 1124–1128).


Solid-state tubular assemblies of thiolactones (I. Vujasinović, J. Veljković, K. Mlinarić-Majerski, K. Molčanov, B. Kojić-Prodić, Tetrahedron 62 (2006) 2868–2876).


compounds (i.e. cimetidine, ranidine, and diltiazem). Since 1985 the Cambridge Structural Database has been available in Croatia via the National Affiliation Centre of Cambridge Crystallographic Data Centre. In 1989 the first diffractometer was purchased. For over forty years chemi- cal crystallography has been combined with spectroscopic met- hods, bio-assays and molecular modelling to understand intramo- lecular and intermole- cular interactions, the topology of hydrogen bonds and the physical properties of chemical and biologically active molecules and their relation to functions. As the activities were more and more concen- trated on biologically


micro- and nanocrystalline materials. New methods for accurate unit-cell parameter measurement have been developed based on the separation of adjacent diffraction lines and by combining single- crystal zero-layer rotation and Weissenberg patterns with powder diffraction patterns. Techniques for quantitative phase analysis of multicomponent sample are being developed. Phase diagrams of semiconductors are related to electrical properties. New high tem- perature phases are characterized. Microstructure and phase dia- grams of a series of mixed metal oxides (e.g. ferrites, orthoferrites, alumina, zirconia, titania) were systematically studied by X-ray powder diffraction, Raman, FT-IR and Mössbauer spectroscopies, in collaboration with the Dept. of Materials Chemistry (RBI). Te processes of biomineralization of bivalvia have been studied in detail in collaboration with the Center for Marine Research (RBI).


Laboratory of Solid State Chemistry, RBI By


ŽeLiMir BLaŽina (blazina@irb.hr) Crystallographic analysis began in the Lab for Solid State Chem-


π–Stacking of quinoid rings, described for the first time, in crystals of ammonium hydrogen chloranilate dihydrate (K. Molčanov, B. Kojić-Prodić, A. Meden, CrystEng- Comm 11 (2009) 1407–1415).


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loids has been used as a standard method for tailoring materials suitable for hydrogen storage purposes. Termodynamic prop- erties of the corresponding inter- metallic compound – hydrogen


istry (formerly High Temperature Materials) at RBI in the 1950s with studies of the crystal morphology and (di)electric properties of Rochelle salt (M. Topić). Subsequently, float zone crystal growth, uranium and thorium ternary silicides and germanides containing transition metals were analyzed with neutron and X-ray powder diffraction methods (M. Tudja). Chemical vapour transport tech- nique was used for preparation of ternary uranium compounds of composition UNTe, UNAs and UAsSb. Powder diffraction analy- sis revealed that they crystallized in the tetragonal structure of the PbFCl type (Z. Despotović, R. Trojko). Te technique of isother- mal transport reaction between metals in molten alkali chloride mixtures was developed and applied to systems containing combinations of Cu, Ni, Ag, Pt, Cr and Fe metals (M. Paljević). Research on multicomponent intermetallic compounds started in the 1970s. A systematic study of phase equilibrium was carried out on selected rare earth – irid- ium systems. Substitution of one or both components in binary intermetallic compounds of the general composition AB2 AB5


and with other metals or metal-


The ThM2


Acta Crystallographica. Ge2 IUCr Newsletter ♦ Volume 19, Number 2 ♦ 2011


structure type published in


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