Crystal Growth, Structural and Thermal Studies of FeC4H4O6·2.5H2O

Abstract

Single crystals of iron(II) tartrate hemi-pentahydrate, FeC4H4O6·2.5H2O, were grown by the gel method using silica gels. Differential scanning calorimetry, thermogravimetric-differential thermal analysis, and X-ray diffraction measurements were performed on the single crystals. The space group symmetry (orthorhombic P212121) and structural parameters were determined at room temperature. The crystal structure consisted of slightly distorted FeO6 octahedra, C4H4O6 and H2O molecules, C4H4O6–Fe–C4H4O6 chains jointed by Fe–O bonds, and O–H···O hydrogen-bonding frameworks between adjacent molecules. Weight losses due to thermal decomposition of the crystal were found to occur in the temperature range of 300–1060 K. We inferred that the weight losses were caused by the evaporation of bound water molecules and the evolution of H2CO, CO, and O2 gases from C4H4O6 molecules, and that the black residue after decomposition was composed of triiron tetraoxide (Fe3O4) and carbon.

Crystal Growth and Structure of NiC4H4O6·2.5H2O

“…Single crystals and polycrystalline aggregates were grown in the gel medium. The polycrystalline aggregates, which were quasi-spherical in shape and green in color, were very similar to those of FeC 4 H 4 O 6 •2.5H 2 O aggregates reported in the previous papers, except for the difference in color (Dhikale, Shitole, Nahire, & Chavan, 2019;Fukami & Tahara, 2022;Mathivanan & Haris, 2013).…”

“…The lattice parameters calculated from all observed X-ray reflections showed that the crystal belongs to the orthorhombic system, and the systematic extinctions indicated that the space group is P2 1 2 1 2 1 . The obtained lattice parameters were similar to those of FeC 4 H 4 O 6 •2.5H 2 O 2022). All non-hydrogen atoms were refined anisotropically, and hydrogen atoms located on difference electron density maps were refined isotropically.…”

“…All structures of tartrate compounds, consisting of divalent cations (from Mn of group 7 to Zn of group 12) belonging to the first transition series, have been elucidated by single crystal X-ray diffraction. Table 5 shows the chemical formulae, space groups, and lattice constants with atomic, ionic, and covalent radii of the cations in the tartrate compounds from articles (Clementi & Raimondi, 1963;Fukami & Tahara, 2020, 2021, 2022Labutina, Marychev, Portnov, Somov, & Chuprunov, 2011;Slater, 1964Slater, , 1965) and Winter's website (Winter, M. J.…”

“…Tartrate compounds are formed by the reaction of tartaric acid with compounds containing positive ions (i.e., two monovalent cations or one divalent cation) (Desai & Patel, 1988;Fukami & Tahara, 2020;Fukami & Tahara, 2021;Fukami & Tahara, 2022;Labutina, Marychev, Portnov, Somov, & Chuprunov, 2011). Tartaric acid (C 4 H 6 O 6 ; systematic name: 2,3-dihydroxybutanedioic acid) has two chiral carbon atoms in its structure, which provides the possibility for four different forms of chiral, racemic, and achiral isomers as follows: L(+)-tartaric, D(-)-tartaric, racemic (DL-) tartaric, and meso-tartaric acid (Bootsma & Schoone, 1967;Fukami, Tahara, Yasuda, & Nakasone, 2016;Song, Teng, Dong, Ma, & Sun, 2006).…”

“…Recently, we reported the crystal growth, structure, and thermal properties of FeC 4 H 4 O 6 •2.5H 2 O (Fukami & Tahara, 2022). The single crystals were grown by the gel method using silica gels.…”