Raman study of phosphate dimerization in aqueous KH₂PO₄ solutions using a self‐deconvolution method

Abstract

A Raman spectroscopic study of aqueous solutions of KH,P04 as a function of concentration and temperature has been made. Attention is focused on the analysis of the bands arising from the internal modes of the H,P04-anions. The band profile of these internal modes has been analysed by a Fourier transform self-deconvolution method which allowed quantitative information about phosphate dimerization to he obtained. The results seem to indicate the existence of two different configurations for the dimers. The association constant for each dimer and their thermodynamic parameters were obtained from the spectroscopic data.

Ion Pairing and Co‐facial Stacking Drive High‐Fidelity Bisulfate Assembly with Cyanostar Macrocyclic Hosts

“…As an alternative explanation, ion pairing alone might be sufficient to enable formation of the anion dimer in solution even without the cyanostar. To the best of our knowledge, no studies of the bisulfate hydroxyanion alone have been undertaken in bulk solution (though there are related studies of dihydrogen orthophosphate and dihydrogen phosphate in water). Consequently, and to test for the idea of ion pairing, we conducted 1 H NMR studies on the NBu 4 HSO 4 salt by itself.…”

Phosphate–phosphate oligomerization drives higher order co-assemblies with stacks of cyanostar macrocycles

“…1a ). Phosphate oligomerization has been seen in solution 38 , 39 even without receptors and was previously modelled 14 in acetonitrile as a simple monomer–dimer equilibrium ( K dimer = 2400 M –1 ) where 66% of the phosphate is dimerized at 1 mM. Presumably, the propensity of phosphate to oligomerize as well as the characteristics of the receptors will help determine the types of complexes it forms.…”

Cluster Formation in Solid-Liquid Interface Boundary Layers of KDP Studied by Raman Spectroscopy

“…It seems unlikely that cation-anion pairing plays an appreciable role in the changes observed in the spectra because there is no evidence from other solutions of electrolytes for strong ion pairing with potassium [7]. In consequence, we can conclude that the changes observed in the spectra arise from the formation of polymer clusters of phosphate anions in the crystal growth solution.…”