Structural and Thermal Investigations of L-CuC4H4O6·3H2O and DL-CuC4H4O6·2H2O Single Crystals

Abstract

Copper(II) L-tartrate trihydrate, L-CuC4H4O6·3H2O, and copper(II) DL-tartrate dihydrate, DL-CuC4H4O6·2H2O, crystals were grown at room temperature by the gel method using silica gels as the growth medium. Differential scanning calorimetry, thermogravimetric-differential thermal analysis, and X-ray diffraction measurements were performed on both crystals. The space group symmetries (monoclinic P21 and P21/c) and structural parameters of the crystals were determined at room temperature and at 114 K. Both structures consisted of slightly distorted CuO6 octahedra, C4H4O6 and H2O molecules, C4H4O6–Cu–C4H4O6 chains linked by Cu–O bonds, and O–H–O hydrogen-bonding frameworks between adjacent molecules. Weight losses due to thermal decomposition of the crystals were found to occur in the temperature range of 300–1250 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 residual reddish-brown substance left in the vessels after decomposition was copper(I) oxide (Cu2O).

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

“…The theoretical weight losses were calculated based on the following considerations. The weight losses in the TG curve of FeC 4 H 4 O 6 •2.5H 2 O may be caused by the evaporation of bound water molecules and the evolution of gases from the sample, similarly to our previous studies (Fukami & Tahara, 2018;Fukami & Tahara, 2020;Fukami & Tahara, 2021). The unit cell of the crystal contains two crystallographically independent formula units, and its chemical formula is expressed as (FeC 4 H 4 O 6 ) 2 •5H 2 O.…”

“…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, 2018;Fukami & Tahara, 2020;Fukami & Tahara, 2021;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: 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).…”

High purity β-Bi2O3 preparation by thermal decomposition of tartrates

“…Thus, in the system "basic bismuth(III) nitrates -solution of L(+)-tartaric acid" under the chosen conditions, bismuth tartrate is not formed. Considering the possibility of using the racemic form of tartaric acid for the synthesis of tartrate precursors [15][16][17], we chose DL-tartaric acid to obtain bismuth tartrate.…”

Crystal Growth and Structure of NiC4H4O6·2.5H2O

“…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).…”