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Novel hydrogen bond-supported intercalation compounds, {(G) m [Fe(CA) 2 (H 2 O) 2 ]} n (CA 2− =chloranilate, G=guest molecules) have been synthesized and characterized. The compound {(Hpy)[Fe(CA) 2 (H 2 O) 2 ](H 2 O)} n (py=pyridine) ( 1 ) crystallizes in the triclinic, space group P 1 (#2), with a =9.537(5), b =13.563(6), c =9.231(4) A, α =107.18(4), β =102.33(4), γ =102.12(4)°, V =1065.9(10) A 3 , and Z =2. Compound {(H 2 bipy)[Fe(CA) 2 (H 2 O) 2 ] 2 (H 2 O) 2 } n (bipy=4,4′-bipyridine) ( 2 ) crystallizes in the triclinic, space group P 1 (#2), with a =9.101(1), b =10.379(1), c =12.802(2) A, α =79.45(1), β =82.67(1), γ =66.32(1)°, V =1086.8(3) A 3 , and Z =1. The structure of 1 consists of mononuclear [Fe(CA) 2 (H 2 O) 2 ] − anions, Hpy + cations and uncoordinated water molecules. Four oxygen atoms of two CA 2− anions and two oxygen atoms from two water molecules are coordinated to the iron ion making anionic building blocks of the host layer. The compound of 2 contains the similar monomeric building blocks, H 2 bipy 2+ cations and uncoordinated water molecules. In both the compounds the coordination geometry of the building blocks are distorted octahedron, where two water molecules sit on the trans position in 1 and on the cis position in 2 . In compound 1 the [Fe(CA) 2 (H 2 O) 2 ] − anions make a two-dimensional (2-D) layer supported by hydrogen bonds. Hpy + ions are included in between the layers of 1 supported by hydrogen-bonding and electrostatic interaction with the host layers. In compound 2 the coordinated chloranilate rings of [Fe(CA) 2 (H 2 O) 2 ] − anions are stacked upon each other and make a layer with the help of hydrogen bonds. H 2 bipy 2+ cations are included in between the layers supported by hydrogen bonding, electrostatic and stacking interaction with coordinated CA 2− ions. The 57 Fe Mossbauer spectra of the compounds show that the oxidation state of iron is 3 with IS=0.41 ( 1 ) and 0.39 mm s −1 ( 2 ); QS=0.83 ( 1 ) and 1.29 mm s −1 ( 2 ) at 296 K, respectively. Compound 2 shows weak antiferromagnetic interaction over the crystal ( θ =−2.3 K). |
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