Naslov
Supramolecular contacts between diamagnetic and paramagnetic [M(bpy)_3]^2+ entities in [M(bpy)_3]_2[NbO(C_2O_4)_3]Cl x nH_2O (M = Fe^2+, Co^2+, Ni^2+, Cu^2+ and Zn^2+ ; n = 11, 12) compounds

Autori
Jurić, Marijana ; Perić, Berislav ; Brničević, Nevenka ; Planinić, Pavica ; Pajić, Damir ; Zadro, Krešo ; Giester, Gerald ; Kaitner, Branko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Sixteenth Croatian-Slovenian Crystallographic Meeting, Book of abstracts and programme / Cetina, Mario ; Popović, Stanko ; Skoko, Željko ; Šantić, Ana ; Štefanić, Zoran - Zagreb : Hrvatska akademija znanosti i umjetnosti (HAZU) ; Hrvatska Kristalografska Zajednica, 2007

Skup
Sixteenth Croatian-Slovenian Crystallographic Meeting

Mjesto i datum
Petrčane, Hrvatska, 13.06.2007. - 17.06.2007

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
supramolecular contacts; magnetism; ligand field

Sažetak
Nine new complex salts of the composition [M(bpy)_3]_2[NbO(C_2O_4)_3]Cl x nH_2O [M = Fe^2+ (1, 2), Co^2+ (3, 4), Ni^2+ (5, 6), Cu^2+ (7) and Zn^2+ (8, 9) ; bpy = 2, 2'-bipyridine ; n = 11 or 12) have been isolated from the reactions of [M(bpy)_3]Cl_2 x nH_2O and [NbO(C_2O_4)_3]^3– . The crystal structures of seven of the compounds (2– 8) have been determined. The compounds make two isostructural sets of pseudopolymorphs crystallizing in the centrosymmetric monoclinic space group P21/c (3, 5, 8) or in the noncentrosymmetric orthorhombic space group P212121 (2, 4, 6, 7). All the structures contain two symmetry independent [M(bpy)_3]^2+ cations (A and B), one [NbO(C_2O_4)_3]^3– anion and one Cl^– anion, and 11 or 12 crystal water molecules (monoclinic and orthorhombic compounds, respectively). The interatomic Fe-N distances in 2 are typical for diamagnetic low-spin Fe^2+ species, the same as are the Co-N distances in 3 and 4 typical for high-spin Co^2+ species. By analysis of the crystal packing in all the structures a specific type of supramolecular contacts between the [M(bpy)_3]^2+ cations has been identified. The contact comprises four bipyridine ligand molecules from two neighbouring [M(bpy)_3]^2+ cations and is termed the quadruple aryl embrace (QAE) contact. This contact is realized by the alignment of two molecular two-fold rotation axes. Influence of aggregation of [M(bpy)_3]^2+ cations via QAE contacts on magnetic properties of these compounds, as well as the influence of trigonal distortion of octahedral coordinations around metal atoms (driven by didendate bpy ligands), has been presented and analyzed.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

POVEZANOST RADA