Sodium oxalate structure refinement

Effect of thermal annealing on synthetic sodium oxalate crystals

“…components in concentrations lower than 3% could be undetected), minor amounts of hydrous phases containing mixtures of sodium oxalate, sodium hydrogen oxalate and oxalic acid cannot be disregarded [16]. The calculated crystallographic data obtained from our XRD results of the oxalate, a o = 10.375, b o = 5.243, c o = 3.449 and˛= = 90.00 •ˇ= 92.66 • that corresponds to a P2 1 /a spatial group, are in good agreement with the previously results described by Reed and Olmstead [4]. The growth of temperature from 200 • C onwards shows subtle structural changes consisting on the formation of new peaks at (1) 3.23Å, (2) 2.91Å and (3) (Fig.…”

“…The C C bond is longer than expected (1.568Å) probably due to the electron density in the * molecular orbital, and Na O bonds are also relatively long (2.4Å) [3]. According to Reed and Olmstead [4] the symmetry is P2 1 /a with unit cell values of a = 10.426(9)Å, b = 5.255(5)Å and c = 3.479(3)Å anď = 93.14(8) • . During the last 15 years, the studies on the thermal stability of oxalates in general have commonly been studied by means of X-ray diffraction (XRD), differential thermal analysis (DTA) and thermogravimetry (TG) [5][6][7].…”

Crystal Structures and Topological Aspects of the High‐Temperature Phases and Decomposition Products of the Alkali‐Metal Oxalates M2[C2O4] (M=K, Rb, Cs)

“…Until recently, only the crystal structures of Li 2 [C 2 O 4 ] [6] and Na 2 [C 2 O 4 ] [7,8] at room temperature had been published. In 2003 we reported the crystal structures of K 2 O 4 ] under ambient conditions, as determined by X-ray powder diffraction.…”

Synthesis and characterization of the oxalate cancrinite-type zeolite

“…The cancrinite and sodalite structures are of prominence as they can potentially provide important insights to the interactions of organic compounds with inorganic solids [3] . Usually, these cancrinite and sodalite-type zeolites, general formula A 8 [B 12 O 24 ]Á2X, can be synthesized using different templating anions, X, such as chloride, sulphate, nitrate, nitrite and a variety of other anions. Earlier work by one of the authors [4] has shown mono and divalent anions with three or fourfold symmetry such as nitrate, sulphate or carbonate can promote the formation of cancrinite-type zeolites.…”