Ni2+ coordination in concentrated aqueous solutions

✍ Scribed by I. Howell; G.W. Neilson

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 651 KB
• Volume: 73-74
• Category: Article
• ISSN: 0167-7322
• DOI: 10.1016/s0167-7322(97)00077-9

✦ Synopsis

Neutron diffraction studies have been carried out on aqueous solutions of 2m nickel sulphate and 4.3 molal nickel nitrate in heavy water. Results derived from the first difference isotopic substitution method show that the Ni*+ hydration is relatively unaffected by the nature of the counterion, albeit, for the sulphate solution, there is a possibility of cation -anion contacts. The cation-cation correlations as defined through gNi,,(r), which is derived from results of second difference experiments, are appreciably different, most noticably in terms of the closest distance of approach of the Ni" cations. Comparison with results for a 4.32 nickel chloride solution shows that the nickel ions in the sulphate and nitrate solutions are more strongly correlated than those for the chloride.