کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1311775 | 975353 | 2006 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Different topologies in heterometallic frameworks of copper(II) with Ni(CN)42- bridging ligand: Syntheses, crystal structures, thermal and magnetic properties Different topologies in heterometallic frameworks of copper(II) with Ni(CN)42- bridging ligand: Syntheses, crystal structures, thermal and magnetic properties](/preview/png/1311775.png)
Four cyano bridged Cu(II)–Ni(II) heterometallic complexes of general formula, [{Cu2(L)2Ni(CN)4}(ClO4)2 · xH2O]n (for 1, L = bis(3-aminopropyl) methylamine = medpt and x = 2.5; for 2, L = N-(2-aminoethyl)-1,3-propanediamine = aepn and x = 2; for 3, L = diethylenetriamine = dien and x = 1), [Cu(medien)Ni(CN)4]n (4) (medien = bis(2-aminoethyl)methylamine) have been synthesized and characterized by single-crystal X-ray diffraction analysis and low temperature magnetic study. In complexes 1–3, all the cyanide ligands of tetracyanonickelate(II) take part in bonding, connecting four adjacent copper(II) ions whereas in 4trans -dicoordinated cyanide of Ni(CN)42- links two Cu(II) ions only. We have already reported, as communication, the structural features of complex 1 and of its dehydrated species 1a. A different chain stereochemistry is detected in the related polymeric frameworks 1–3, mainly dictated by the orientation assumed by the ancillary tridentate L ligand. Thermogravimetric analyses and X-ray powder diffraction of complexes 1–3 reveal that the complexes retain their crystallinity upon removal of lattice water molecules. The magnetic studies of complexes 1–4 were performed in the 2–300 K temperature range. For all the complexes, the χMT values from 300 to 60 K are very close and correspond to isolated Cu(II) ions with different average g values (>2.00). From 60 to 2 K, χMT values decrease indicating weak antiferromagnetic coupling.
Four cyano bridged Cu(II)–Ni(II) heterometallic complexes have been synthesized and characterized by single-crystal X-ray diffraction analysis and low temperature magnetic study. Some of them retain their crystallinity upon removal of lattice water molecules and exhibit selective solvent inclusion properties.Figure optionsDownload as PowerPoint slide
Journal: Inorganica Chimica Acta - Volume 359, Issue 2, 20 January 2006, Pages 593–602