Design of Novel Inorganic−Organic Hybrid Materials Based on Iron-Chloranilate Mononuclear Complexes:  Characteristics of Hydrogen-Bond-Supported Layers toward the Intercalation of Guests

• Published in: Journal of the American Chemical Society Vol. 125; no. 1; pp. 221 - 232
• Main Authors: Nagayoshi, Kunimitsu, Kabir, Md. Khayrul, Tobita, Hiroshi, Honda, Kenji, Kawahara, Mitsuhiro, Katada, Motomi, Adachi, Keiichi, Nishikawa, Hiroyuki, Ikemoto, Isao, Kumagai, Hitoshi, Hosokoshi, Yuko, Inoue, Katsuya, Kitagawa, Susumu, Kawata, Satoshi
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 08-01-2003
• Subjects: Chemistry; Condensed matter: structure, mechanical and thermal properties; Coordination compounds; Exact sciences and technology; Inorganic chemistry and origins of life; Inorganic compounds; Metal complexes; Physics; Preparations and properties; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Molecular packing; Iron Complexes; Molecular structure; EPR spectrometry; TTF; Organic ligand; Molecular interaction; Anionic complex; Moessbauer spectrometry; Transition metal Complexes; X ray diffraction; Phenazine; Aqua complex; Complexes Mixed; Raman spectrometry; Magnetic properties; Crystalline structure
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja027895v

Novel intercalation compounds constructed from the common two-dimensional hydrogen-bond-supported layers and functional guests {(H0.5phz)2[Fe(CA)2(H2O)2]·2H2O} n (1), {[Fe(Cp)2][Fe(CA)2(H2O)2]} n (2), {[Fe(Cp*)2][Fe(CA)2(H2O)2]} n (3), and {(TTF)2[Fe(CA)2(H2O)2]} n (4) (H2CA = chloranilic acid, phz = phenazine, [Fe(Cp)2] = ferrocene, [Fe(Cp*)2] = decamethylferrocene, TTF = tetrathiafulvalene) are described. The guest cations are introduced between the {[Fe(CA)2(H2O)2]m-}l layers by electrostatic (1 − 4) and π−π stacking (3, 4) interactions. [Fe(Cp*)2]+ cations in 3 are stacked on each other making tilted columns which are included in the channel created by the chlorine atoms of CA2- dianions. TTF cations in 4 are stacked face to face with two types of S···S distances (type A; 3.579(3) Å, and type B; 3.618(3) Å) making a columnar structure. The TTF cations in the stacked column have a head-to-tail arrangement with respect to the iron-chloranilate layer. Mössbauer spectroscopy suggests that [Fe(CA)2(H2O)2]m- anion in 3 is consistent with high-spin (S = 5/2) iron(III) ions and [Fe(Cp*)2]+ in the low-spin (S = 1/2) iron(III) ions. In 4, Mössbauer spectroscopy shows high-spin iron(II) ions (IS = 1.10 mm·s-1 and QS = 1.66 mm·s-1 at 297 K) and high-spin iron(III) ions (IS = 0.42 mm·s-1 and QS = 1.27 mm·s-1 at 297 K), suggesting that the anionic layer of iron-chloranilate has a valence-trapped mixed-valence state. At the temperature range of 77−300 K, the compounds 1, 2, and 3 are EPR silent, whereas the EPR spectrum of 4 shows two types of signals with g = 2.008 indicating the radical form of TTF.