Crystal structure ammonium salts

Determination of the influence of crystal structure and reactant environment on deammination and dehydration processes is complicated by the several solid phase transformations that are a characteristic feature of many ammonium salts. Sublimation and/or melting may also occur. Deammination and dehydration steps are generally reversible. At high temperatures, however, particularly in the presence of a residual oxide... 

The results of a vibrational spectroscopic study of the SO2 complexes [RuX(S02)(NH3)4]" (X = Cl, Br) and [Ru(H20)(S02)NH3)4] + have been reported the j/(sym) and j/(asym) modes of the 5 -bound SO2 ligand come at lower frequencies than those of the free molecule. The ammonium salt of the sulfito complex tra 5-[Ru(S03-5)2(NH3)4] 4H20 has been structurally characterized. Although the crystals are stable when retained in the mother liquor, the isolated compound is only stable at 298 K for several days. Relationships between the structural and vibrational spectroscopic data are discussed. ... 

NH4]-3H20 upon 5 min exposure to vapours of aqueous ammonia 30%. Single crystals of the ammonium salt for X-ray structure determination can be obtained if the reaction of the zwitterion with ammonia is carried out in aqueous solution. As in the case of the chloride salt, formation of [Co (q - 5114000)2] [NH4] 3H20 in the heterogeneous reaction is assessed by comparison of the observed and calculated X-ray powder diffraction patterns. Absorption of ammonia is also fully reversible upon thermal treatment (1 h at... 

Normal isopoly- and peroxymolydates of ammonium and several metals are known. The normal or orthomolybdates may be considered as salts of molybdic acid having formulas H2Mo04 xH20 or M20 Mo03 xH20. They are either of monoclinic or scheelite type crystal structure and obtained as hydrated salts. 

Ammonium dinitramide (ADN) and hydrazinium nitroformate (HNF) are potential high performance and eco-friendly replacements for AP in composite propellants and efforts are being made all over the globe in this direction. Similarly, there is a need to study these high performance oxidizers and their salts for pyrotechnic applications. Some groups of researchers have already initiated research in this direction and several alkali dinitramide salts have been synthesized and characterized for their elemental content, solubility, thermal behavior and crystal structures. 

Preparation of a Complex Ammonium Salt of Copper(II). Dissolve 0.5 g of finely triturated copper(II) sulphate pentahydrate in 12.5 ml of a 15% ammonia solution. If the solution is turbid, filter it. Slowly add 7.5 ml of ethanol to the filtrate and let it stand for a few hours in the cold. Filter off the formed crystals, wash them first with a mixture of ethanol and a concentrated ammonia solution (1 1), and then with ethanol and ether. Dry them at room temperature. Into what ions does the product dissociate in the solution Consider the structure of the complex ion from the viewpoint of the valence bond theory. 

Bis(dialkyldithiophosphinato)nickel(II) complexes were prepared by the direct synthesis of an alkali metal or ammonium salt of the dithiophosphinic acid and a nickel salt in aqueous solution.2039,2061"2063 Ni(S2AsR2)2 and Ni(Se2PR2)2 complexes were prepared in a similar way.2064"2066 All of these complexes are square planar like their dithiophosphate analogues. X-Ray crystal structures of the complexes Ni(S2PR2)2, with R = Me,2067 Et, Ph,1983 R2 = Me/ Et 2°w r2 = Me/2-thienyl,2069 and Ni(Se2PPh2)21984 have been reported (Table 90). 

The single crystal X-ray structure analysis of the trimethyltin-substituted ammonium salt [H2N(SnMe3)2][SnMe3Cl2] (115)247 was also reported. In compound 115 the anion... 

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