Magnetic Properties of Cu₂(OH)₃(alkanecarboxylate) Compounds:  Drastic Modification with Extension of the Alkyl Chain

Abstract

Magnetic properties of the layered materials Cu 2 (OH) 3 (n-C m H 2m+1 COO) (m ) 0, 1, 7, 8, and 9) have been examined. X-ray powder diffraction patterns indicate that the interlayer distance increases in the order of m. The interlayer distances of the m ) 0 and 1 materials are shorter than the molecular heights of the intercalated carboxylates, respectively, while the distances of the m ) 7-9 materials are nearly double those of the molecular heights of the corresponding carboxylates, indicating a bilayer structure in them. The temperature dependence of the paramagnetic susceptibilities of the m ) 0 and 1 materials suggests an intralayer ferromagnetic interaction and an interlayer antiferromagnetic interaction. The metamagnetic behavior is supported by S-shape dependence of their magnetization curves. The temperature dependence of the paramagnetic susceptibilities of the m ) 7-9 materials indicates an intralayer antiferromagnetic interaction, in opposition to those in the former two. Further, they show a divergence of the ac magnetic susceptibility at 22 K, indicating a ferromagnetic order. The magnetization curve is characterized by an immediate increase at lower fields, succeeded by a gradual increase without saturation at higher fields. The magnetic properties of the m ) 7-9 materials are well understood in terms of the weak ferromagnetism. The change of the intralayer magnetic interaction could be caused by some structural change in the CuOH layer with the intercalation.

Hydroxy Double Salt Anion Exchange Kinetics: Effects of Precursor Structure and Anion Size

“…The magnetic properties of intercalated copper hydroxides have been shown to exhibit a striking dependence on the interlayer spacing. [2][3][4] Hydroxy double salts, HDSs, are another more recently emerging class of compounds that hold similar promise for development as new nanostructured materials for a wide range of applications. HDSs, [(M 2+ 1 - x,Me 2+ 1+x)(OH)3(1 - y)] + A n-(1+3y)/n· zH2O, are similar to LDHs except that the metal hydroxide layer contains two divalent metals, designated here as M 2+ and Me 2+ .…”

Structural and spectroscopic study of organic-inorganic transition metal based layered magnets

“…The layered compounds M 2 (OH) 3 A (M = Co, Cu, and A = NO 3 -or OAc -) are shown to be well adapted for substitution reactions [9][10][11][12]. The exchange for large organic species (i.e.…”

“…The exchange for large organic species (i.e. aliphatic chain anions) coordinating the metal ion enables to tune the basal spacing, and accordingly to modify drastically the magnetic properties [11,12]. Thus, nalkyl chain molecules involving a single anionic function (carboxylate or sulfate anion), have been used to separate basic layers (Fig.…”

Design and Synthesis of New Functional Materials Using the Interstices of Inorganic Host Structure

“…37) Another new anion exchangeable layered compound with a composition of Ni 1|x Zr 2x (OH) 2 (OCOCH 3 ) 2x« nH 2 O was pre pared by hydrothermal hydrolysis of NiZn mixed acetate solutions. 38) The structure is related to zinc basic salt, Zn 5 (OH) 8 Cl 2 EnH 2 O; as shown in Fig.…”