Disodium , crystal structure

The larger-ringed macrocycles of (53a-d) form binuclear complexes with alkali metal, alkaline earth, silver(I) and lead(II) cations.68,192 The two 18-membered rings are large enough to allow for cations as large as Rb+ to be incorporated within their cavity, with a net result of increasing the metal-metal separation. Thus, crystal structure data for the disodium complex of (53a) indicate the sodium ions to be 6.40 A apart,193,194 compared to a 3.88 A separation found for the aforementioned disilver complex of (52a). Heteronuclear complex formation has also been observed, e.g. with both Ag+ and Pb2+ incorporated in the same cryptand.192... 

Two complexes containing a dilithiated stilbene fragment have been prepared and isolated from the reactions of 1,2-diphenylethane with N-chelated butyl-lithium reagents. " The molecular and crystal structures of these compounds, stilbene bis(lithium tetramethylethylenediamine) (Figure 4a) and stilbene bis(lithium pentamethyldiethylenetriamine) (Figure 4b), have been determined by X-ray diffraction techniques. Each structure contains two amine-solvated Li atoms located above and below the olefinic bond of a stilbene molecule. The stilbene molecule is planar in both structures, and is in a trans configuration about the C(7)—C(7 ) bond, which is ca. 0.01 nm longer than that in trans-stilbene. " The optical and "C n.m.r. spectra of THF solutions of the related dilithium and disodium salts of tetraphenylethylene dianion, as well as the spectra of their mixtures, have been examined. " The data can be rationalized in terms of the... 

Sanz F, Parada C et al (2001) Crystal growth, crystal structure and magnetic properties of disodium cobalt fluorophosphate. J Mater Chem 11 208-211... 

Eor the purpose of scale removal, disodium EDTA (Na HjEDTA) and tetrasodium EDTA (Na EDTA) are the most effective. They are the most cost-effective as well, relative to the other EDTA salts (and carhoxylates). While disodium EDTA is not nearly as cost-effective as HCl, it has other advantages. Unlike HCl, disodium EDTA can dissolve CaSO. Solubility depends on the crystal structure. EDTA treatments for scale removal also can prevent rapid redeposition of scale. ... 

The molecular structure of arsphenamin is a typical representative of a thermotropic mesogen. With its symmetrical arrangement of the atoms the same holds for disodium cromoglycate, DNCG [20], which forms both thermotropic liquid crystals and lyotropic mesophases in the presence of water. Micronized DNCG powder applied to the mucosa of the nose or the bronchi absorbs water from the high relative humidity of the respiration tract and is first transformed into a lyotropic mesophase and then into a solution depending on the amount of water available. 

Disodium Tetraborate Tetrahydrate. Disodium tetraborate tetrahydrate, Na I C TH O or Na20 2B203 4H20, formula wt, 273.27 monoclinic sp gr, 1.908 specific heat, ca 1.2 kJ/(kg K) [0.287 kcal/(g °C)] (61) heat of formation, —4.4890 MJ/mol ( — 1072.9 kcal/mol) (69) exists in nature as the mineral kemite and has a structural formula Na2[B40 (0H)2] 3H20. The crystals have two perfect cleavages and when ground, form elongated splinters. 

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