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arXiv · 1710.06376

Temperature dependence of the hydrogen bond network in Trimethylamine N-oxide and guanidine hydrochloride - water solutions

Felix Lehmkühler·Yury Forov·Mirko Elbers·Ingo Steinke·Christoph J. Sahle·Christopher Weis·Naruki Tsuji·Masayoshi Itou·Yoshiharu Sakurai·Christian Sternemann
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Abstract

We present an X-ray Compton scattering study on aqueous Trimethylamine N-oxide (TMAO) and guanidine hydrochloride solutions (GdnHCl) as a function of temperature. Independent from the concentration of the solvent, Compton profiles almost resemble results for liquid water as a function of temperature. However, The number of hydrogen bonds per water molecule extracted from the Compton profiles suggests a decrease of hydrogen bonds with rising temperatures for all studied samples, the differences between water and the solutions are weak. Nevertheless, the data indicate a reduced bond weakening with rising TMAO concentration up to 5M of 7.2% compared to 8 % for pure water. In contrast, the addition of GdnHCl appears to behave differently for concentrations up to 3.1 M with a weaker impact on the temperature response of the hydrogen bond structure.

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Felix Lehmkühler, Yury Forov, Mirko Elbers, Ingo Steinke, Christoph J. Sahle, Christopher Weis, Naruki Tsuji, Masayoshi Itou, Yoshiharu Sakurai, Christian Sternemann. 2017-10-17. Temperature dependence of the hydrogen bond network in Trimethylamine N-oxide and guanidine hydrochloride - water solutions. https://doi.org/10.1039/c7cp04958g

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