Magnetic behavior of polycarbosilazane FeII, FeIII and mixed-valence FeII-III chloride metallopolymers

• Published in: Polymer international Vol. 56; no. 3; pp. 376 - 380
• Main Authors: Ali Hamam, Yaqoub, El Ghanem, Hasan Moh'd, Mahmoud Arafa, Issam, Said, Moh'd Rida, aljarayish, Ibrahim Abo
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01-03-2007
• Subjects: iron-polycarbosilazane complex; macromolecular iron complex; magnetic polymer; magnetization; metallopolymer; organosilicon polymer
• ISSN: 0959-8103; 1097-0126
• DOI: 10.1002/pi.2157

FeII, FeIII and mixed‐valence FeII–III chlorides were reacted with poly[N,N′‐bis(dimethylsilyl)ethylenedi‐ amine], [Si(CH3)2NHCH2CH2NH]n, to form the corresponding Fe‐polycarbosilazane macromolecular complexes. The average chain–chain spacing in these materials was estimated from X‐ray diffraction data and found to be 6.94, 7.29, 7.30 and 7.45 Å in metal‐free and FeII, FeIII and FeII–III‐containing polycarbosilazanes, respectively. This demonstrates that FeII, FeIII and FeII–III chlorides are encapsulated between the polycarbosilazane chains. The chain–chain expansions in the divalent FeII and trivalent FeIII chloride macromolecular complexes are comparable, but less than that in the FeII–III chloride analog, which suggests that different chain–chain packings exist in the mixed‐valence macromolecular complex. The magnetic properties of the resulting complexes were investigated by measuring the magnetization in magnetic fields up to 8 kOe and in the temperature range from liquid nitrogen temperature to room temperature. Copyright © 2007 Society of Chemical Industry