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New complexes of DMAN proton sponge with 3 dicarboxylic acids (dca): glutaric {1}, suberic {2} and dodecanedioic acid {3} were obtained. The structures of the complexes {1,2} were solved on the basis of laboratory powder data, while the structure of {3} was solved using single crystal methods. The additional goal of the study was to test some new approaches to organic crystal structure solution from powder diffraction data, particularly with presence of molecules with high number of internal rotational degrees of freedom (dca molecules). Performance of structure solution using the popular FOX program was tested with alternative definitions of flexible dca molecules.

Two hybrid organic-inorganic materials, ZnS(1,3-diaminopropane)1/2 {1} and ZnSe(m-xylylenediamine)1/2 {2} were used as precursors of nanometric ZnS and ZnSe nanostructures. To obtain a single-phase semiconductor, refluxing in different solvents (acetonitrile, 1-octanol, 1,6-hexanediol) with various boiling points was applied. In this method, the synergic effect between temperature and the properties of the reactant medium was used to remove amines from hybrid material containing semiconducting slabs and to form pure nanometer-sized semiconducting grains whose properties were different than those of the corresponding bulk phases. The main goal of our research was to answer the question whether reaction conditions have an impact on the features of obtained semiconducting grains of ZnS and ZnSe. Accordingly, all obtained samples were analyzed using the powder diffraction method, UV-vis spectroscopy and scanning electron microscopy.

Using synchrotron powder diffraction data, two new complexes of CdBr2 with 3-fluoroaniline and 4-fluoroaniline were fully characterised with regard to their structure. Their crystal structures were solved and refined by means of powder diffraction techniques. The investigated materials belong to the group of hybrid inorganic–organic coordination polymers. The structures of both compounds are created by the same type, infinite chains formed by CdBr4N2 octahedra. Each cadmium cation is surrounded by four Br− anions, and two N atoms from two fluoroaniline molecules. The obtained structural data enable us to investigate the influence of the position of the F atom in the aniline ring on the crystal structure, as well as to interpret its thermal stability.

Hybrid organic-inorganic materials of the type (diamine)MeSO4 (Me = Cd, Zn) [diamine = p-xylylenediamine (PXDA) or m-xylylenediamine (MXDA)] have not been described in the literature to date. Four compounds of this type, namely, (MXDA)ZnSO4 (1), (MXDA)CdSO4 (2), (PXDA)ZnSO4 (3), and (PXDA)CdSO4 (4), were synthesized by solvothermal methods. Since all compounds crystallized as very fine powders, crystal structure studies were performed using powder diffraction methods. All compounds crystallize in the orthorhombic crystal system and the cell parameters are: a = 9.8004(4) Å, b = 10.7829(3) Å, c = 4.88473(19) Å for 1; 9.8824(10), 11.0907(7), 4.9663(5) Å for 2; 9.8496(3), 21.2419(5), 4.89556(17) Å for 3; and 10.1136(4), 21.6625(3), 4.9562(2) Å for 4. The compounds with MXDA as a linker, crystallize in the space group P21ma, those with PXDA in Pnma. These hybrid materials are built of inorganic monolayers [–Me–(SO4)–] joined by organic linkers created by diamines (PXDA or MXDA). Me metal ions and SO42– anions form layers with a honeycomb structure. In addition to crystal structure, chemical analyses and SEM investigations were performed. Thermal stability of the compounds was also investigated using TG-DSC methods and XRD as a function of temperature.

This paper discusses and compares molecular interactions of rhodanine (Rd), the heterocyclic compound containing N, S, and O atoms, with two forms of silver species, i.e. Ag(I) ions and silver nanocolloidal particles. Vibrational spectroscopic and powder crystallography studies on coordination of Ag(I) ions in the solid state, supported by density functional theory, clearly indicate complexation through the nitrogen (the deprotonated imino group) and exocyclic sulfur atoms. Molecules of the complex arearranged in a one-dimensional infinite polymeric chain structure that intertwines to give a helixmotif. On the other hand, adsorption geometry of Rd on the silver surface was determined by using surface-enhancement Raman scattering (SERS) spectroscopy.Observed differences between the SERS and the normal Raman spectra of Rd suggest that Rd adsorbs on the silver species after the rearrangement of the keto-thione form into the enolthiol tautomer in acidic and neutral solutions. This leads to adsorption on this silver species through the thiolate ion. On the other hand, the alkaline pH forces first N-deprotonation of Rd, and, in consequence, the obtained anion of the keto-thione form interacts with the silver surface as a result of the presence of lone pairs of nitrogen andsulfur atoms, similar to thecase discussed for the solid state.