An experimental and theoretical study on the interaction of PHBA ions and H2O molecules

We studied the dependence of the Raman spectra on the concentration of PHBA aqueous solution under UV laser excitation. Through analyzing the spectra, we conclude that the interaction between PHBA ions and H2O molecules is weak. To further explore the problem, we studied the interaction between PHBA ions and H2O molecules by virtue of theoretical calculations, DFT-B3PW91/6-31+g* was employed. We draw a coincident conclusion with the experiments and dug out the reasonable interaction model that reflects the actual interaction configuration between PHBA ions and H2O molecules. We supply a new thinking for studying interactions between solute molecules and solvent molecules, which also can be applied to interactions between solute molecules and other solute molecules in solutions.